将长度值从一个 Activity 传递到另一个时出现数组初始化错误
Array initialization error while passing length value from one Activity to another
我是 Android 开发的新手。
我正在使用 Intent.
从 Activity 传递一个值（int 类型）
Intent intent = new Intent(this, NewActivity.class);
intent.putExtra("length", length); //value is taken from a edit text
startActivity(intent);
然后在 NewActivity 中，我在 onCreate() 方法中添加了这段代码。
arrayLength = getIntent().getIntExtra("length", 0); //int type arrayLength variabel is diclared globally.
然后我尝试在 NewActivity 上初始化一个数组（功能失效）为：
char[] array = new char[arrayLength];
然后我在循环中添加数组元素并尝试使用 Button 在 TextView 中显示。
但是，当我单击 Button 以使用以下代码行显示数组元素时，我的应用程序崩溃了：
arrayElemtsShow.setText(new String (array));
But if I initialize this array with a constant like below, it works fine.
char[] array = new char[20];
但重要的是使用前一个 Activity 的值初始化这个数组。
我该怎么做才能解决这个问题？
为什么会这样？
Logcat:
> 2020-06-03 08:43:41.449 30912-30912/? I/.aam.secretnam: Late-enabling
> -Xcheck:jni 2020-06-03 08:43:41.721 30912-30912/com.aam.secretname I/Perf: Connecting to perf service. 2020-06-03 08:43:41.836
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method
> Landroid/graphics/drawable/Drawable;->getOpticalInsets()Landroid/graphics/Insets;
> (light greylist, linking) 2020-06-03 08:43:41.836
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> field Landroid/graphics/Insets;->left:I (light greylist, linking)
> 2020-06-03 08:43:41.836 30912-30912/com.aam.secretname
> W/.aam.secretnam: Accessing hidden field
> Landroid/graphics/Insets;->right:I (light greylist, linking)
> 2020-06-03 08:43:41.836 30912-30912/com.aam.secretname
> W/.aam.secretnam: Accessing hidden field
> Landroid/graphics/Insets;->top:I (light greylist, linking) 2020-06-03
> 08:43:41.836 30912-30912/com.aam.secretname W/.aam.secretnam:
> Accessing hidden field Landroid/graphics/Insets;->bottom:I (light
> greylist, linking) 2020-06-03 08:43:41.970
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method
> Landroid/view/View;->computeFitSystemWindows(Landroid/graphics/Rect;Landroid/graphics/Rect;)Z
> (light greylist, reflection) 2020-06-03 08:43:41.973
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method Landroid/view/ViewGroup;->makeOptionalFitsSystemWindows()V
> (light greylist, reflection) 2020-06-03 08:43:41.986
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method
> Landroid/widget/TextView;->getTextDirectionHeuristic()Landroid/text/TextDirectionHeuristic;
> (light greylist, linking) 2020-06-03 08:43:42.217
> 30912-30938/com.aam.secretname I/Adreno: QUALCOMM build
> : 4e21c4c, I21281c58c8
> Build Date : 03/01/19
> OpenGL ES Shader Compiler Version: EV031.25.03.02
> Local Branch :
> Remote Branch : refs/tags/AU_LINUX_ANDROID_LA.UM.7.5.R1.09.00.00.464.039
> Remote Branch : NONE
> Reconstruct Branch : NOTHING 2020-06-03 08:43:42.217 30912-30938/com.aam.secretname I/Adreno: Build Config
> : S L 6.0.7 AArch32 2020-06-03 08:43:42.222
> 30912-30938/com.aam.secretname I/Adreno: PFP: 0x005ff110, ME:
> 0x005ff066 2020-06-03 08:43:42.227 30912-30938/com.aam.secretname
> I/ConfigStore:
> android::hardware::configstore::V1_0::ISurfaceFlingerConfigs::hasWideColorDisplay
> retrieved: 0 2020-06-03 08:43:42.227 30912-30938/com.aam.secretname
> I/ConfigStore:
> android::hardware::configstore::V1_0::ISurfaceFlingerConfigs::hasHDRDisplay
> retrieved: 0 2020-06-03 08:43:42.227 30912-30938/com.aam.secretname
> I/OpenGLRenderer: Initialized EGL, version 1.4 2020-06-03 08:43:42.227
> 30912-30938/com.aam.secretname D/OpenGLRenderer: Swap behavior 2
> 2020-06-03 08:43:42.370 30912-30912/com.aam.secretname
> I/AssistStructure: Flattened final assist data: 2924 bytes, containing
> 1 windows, 10 views 2020-06-03 08:43:46.687
> 30912-30912/com.aam.secretname I/Timeline: Timeline:
> Activity_launch_request time:527917018 2020-06-03 08:43:46.728
> 30912-30912/com.aam.secretname W/ActivityThread:
> handleWindowVisibility: no activity for token
> android.os.BinderProxy@22a035f 2020-06-03 08:43:51.641
> 30912-30912/com.aam.secretname D/AndroidRuntime: Shutting down VM
> 2020-06-03 08:43:51.645 30912-30912/com.aam.secretname
> E/AndroidRuntime: FATAL EXCEPTION: main
> Process: com.aam.secretname, PID: 30912
> java.lang.IllegalStateException: Could not execute method for android:onClick
> at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:402)
> at android.view.View.performClick(View.java:6608)
> at android.view.View.performClickInternal(View.java:6585)
> at android.view.View.access00(View.java:785)
> at android.view.View$PerformClick.run(View.java:25919)
> at android.os.Handler.handleCallback(Handler.java:873)
> at android.os.Handler.dispatchMessage(Handler.java:99)
> at android.os.Looper.loop(Looper.java:201)
> at android.app.ActivityThread.main(ActivityThread.java:6826)
> at java.lang.reflect.Method.invoke(Native Method)
> at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
> at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
> Caused by: java.lang.reflect.InvocationTargetException
> at java.lang.reflect.Method.invoke(Native Method)
> at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:397)
> at android.view.View.performClick(View.java:6608)
> at android.view.View.performClickInternal(View.java:6585)
> at android.view.View.access00(View.java:785)
> at android.view.View$PerformClick.run(View.java:25919)
> at android.os.Handler.handleCallback(Handler.java:873)
> at android.os.Handler.dispatchMessage(Handler.java:99)
> at android.os.Looper.loop(Looper.java:201)
> at android.app.ActivityThread.main(ActivityThread.java:6826)
> at java.lang.reflect.Method.invoke(Native Method)
> at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
> at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
> Caused by: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
> at com.aam.secretname.FirstInput.getLineNumbers(FirstInput.java:71)
> at com.aam.secretname.FirstInput.line3(FirstInput.java:57)
> at java.lang.reflect.Method.invoke(Native Method)
> at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:397)
> at android.view.View.performClick(View.java:6608)
> at android.view.View.performClickInternal(View.java:6585)
> at android.view.View.access00(View.java:785)
> at android.view.View$PerformClick.run(View.java:25919)
> at android.os.Handler.handleCallback(Handler.java:873)
> at android.os.Handler.dispatchMessage(Handler.java:99)
> at android.os.Looper.loop(Looper.java:201)
> at android.app.ActivityThread.main(ActivityThread.java:6826)
> at java.lang.reflect.Method.invoke(Native Method)
> at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
> at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
第一classxml
<TextView
android:id="@+id/textView5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fontFamily="serif-monospace"
android:gravity="center"
android:padding="4dp"
android:text="@string/length"
android:textColor="#66B1F3"
android:textSize="24sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.243" />
<EditText
android:id="@+id/editText"
android:layout_width="200dp"
android:layout_height="40dp"
android:autofillHints=""
android:ems="10"
android:background="@drawable/stroke"
android:gravity="center"
android:hint="@string/Enterlength"
android:inputType="textPersonName"
android:textColor="#FFFFFF"
android:textSize="20sp"
app:layout_constraintBottom_toTopOf="@+id/button2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.497"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView5"
app:layout_constraintVertical_bias="0.122" />
<Button
android:id="@+id/button2"
android:layout_width="300dp"
android:layout_height="wrap_content"
android:layout_marginBottom="44dp"
android:onClick="nextOnClick"
android:text="@string/btnnext"
android:background="@drawable/radius_button"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.491"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="@+id/btnexample"
android:layout_width="150dp"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"
android:background="@drawable/radius_button"
android:fontFamily="serif"
android:text="@string/examplebtn"
android:visibility="invisible"
android:textAllCaps="false"
android:textSize="18sp"
android:onClick="exampleOnClick"
app:layout_constraintBottom_toTopOf="@+id/button2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.781"
app:layout_constraintStart_toStartOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
第二个classXml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/gradient_background">
<TextView
android:id="@+id/textView6"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fontFamily="sans-serif-condensed-medium"
android:gravity="center"
android:padding="4dp"
android:text="@string/instruction"
android:textColor="#2E183E"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.023" />
<Button
android:id="@+id/button3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line1"
android:text="@string/alphabet_1"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView7" />
<Button
android:id="@+id/button4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line6"
android:text="@string/alphabet_6"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button5"
app:layout_constraintVertical_bias="0.0" />
<Button
android:id="@+id/button5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line5"
android:text="@string/alphabet_5"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button6" />
<Button
android:id="@+id/button6"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line4"
android:text="@string/alphabet_4"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button7" />
<Button
android:id="@+id/button7"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line3"
android:text="@string/alphabet_3"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button8" />
<Button
android:id="@+id/button8"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line2"
android:text="@string/alphabet_2"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button3" />
<Button
android:id="@+id/button9"
android:layout_width="150sp"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
android:layout_marginBottom="8dp"
android:background="@drawable/radius_button"
android:onClick="nextOnClick"
android:text="@string/btnnext"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
<TextView
android:id="@+id/textView7"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/stroke"
android:gravity="center"
android:hint="@string/line_numbers"
android:padding="2dp"
android:textColor="#fff"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView6" />
<Button
android:id="@+id/button10"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:layout_marginStart="24dp"
android:layout_marginLeft="24dp"
android:layout_marginBottom="4dp"
android:background="@drawable/back_button"
android:onClick="reset"
android:text="@string/reset"
android:textSize="16sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="@+id/button20"
android:layout_width="150dp"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
android:layout_marginBottom="8dp"
android:background="@drawable/radius_button"
android:fontFamily="serif"
android:text="@string/examplebtn"
android:textAllCaps="false"
android:textSize="18sp"
app:layout_constraintBottom_toTopOf="@+id/button9"
app:layout_constraintEnd_toEndOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
第一个class
package com.aam.secretname;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class LengthActivity extends AppCompatActivity {
//variables
int length = 0;
Intent intent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_length);
}
public void nextOnClick(View view) {
getLength();
if ((length > 0) && (length < 20)) {
intent = new Intent(LengthActivity.this, FirstInput.class);
intent.putExtra("length", length); //sending value in second activity
startActivity(intent);
}
}
public void exampleOnClick(View view) {
TextView showInfo = (TextView) findViewById(R.id.textView5);
Button example = (Button) findViewById(R.id.btnexample);
showInfo.setText(R.string.example);
example.setVisibility(View.INVISIBLE);
}
private void getLength() {
try {
EditText wordLength = (EditText) findViewById(R.id.editText);
int tempLength = Integer.parseInt(wordLength.getText().toString());
if ((tempLength<20) && (tempLength>0)) {
length = tempLength;
}
else {
TextView showInfo = (TextView) findViewById(R.id.textView5);
showInfo.setTextColor(Color.RED);
if (tempLength == 0) showInfo.setText(R.string.warningOfLenthZero);
else showInfo.setText(R.string.warningOfLengthLimitation);
}
}
catch (Exception e){
TextView showInfo = (TextView) findViewById(R.id.textView5);
Button example = (Button) findViewById(R.id.btnexample);
showInfo.setTextColor(Color.RED);
showInfo.setText(R.string.instuctForGivingLength);
example.setVisibility(View.VISIBLE);
}
}
}
第二个Class
package com.aam.secretname;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
import java.util.Arrays;
public class FirstInput extends AppCompatActivity {
//variables
int wordLength;
static int count = 0;
char[] lineNumbers = new char[wordLength]; //problem
Intent intent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first_input);
wordLength = getIntent().getIntExtra("length", 0); //receiving value of previous activity
}
public void nextOnClick(View view) {
intent = new Intent(FirstInput.this, FinalInput.class);
if (lineNumbers[wordLength - 1] != '[=20=]'){
intent.putExtra("lineNumbers", new String(lineNumbers));
intent.putExtra("length", wordLength);
startActivity(intent);
}
else {
TextView warning = (TextView) findViewById(R.id.textView6);
warning.setTextColor(Color.RED);
warning.setText(R.string.instuctionForTappingOnLine);
}
}
public void reset(View view) {
count = 0;
Arrays.fill(lineNumbers, '[=20=]');
Toast.makeText(this, "Reseted", Toast.LENGTH_SHORT ).show();
TextView showLineNumbers = (TextView) findViewById(R.id.textView7);
showLineNumbers.setText("");
}
public void line1(View v){
getLineNumbers('1');
}
public void line2(View v){
getLineNumbers('2');
}
public void line3(View v){
getLineNumbers('3');
}
public void line4(View v){
getLineNumbers('4');
}
public void line5(View v){
getLineNumbers('5');
}
public void line6(View v){
getLineNumbers('6');
}
private void getLineNumbers(char line) {
if(count < wordLength){
lineNumbers[count++] = line;
TextView showLineNumbers = (TextView) findViewById(R.id.textView7);
showLineNumbers.setText(new String(lineNumbers));
}
else{
TextView showInfo = (TextView) findViewById(R.id.textView6);
showInfo.setText(R.string.completedInput);
}
}
}
您应该提供例外情况logcat；但我猜你在从 EditText
中获取值时错过了将 String 转换为 int
intent.putExtra("length", Integer.parseInt(length));
UPDATE:
您的问题是您将 lineNumbers 数组初始化为具有 0 个值的成员；这是因为 java 中的默认 int 值为 0。
因此，当您使用下面的声明语句时，您正在为 lineNumbers 数组分配一个长度为 0 的值，因为 wordLength 是 s 直到 0；所以你需要做的是在你 getIntent().getIntExtra() 值之后做这个作业。
在代码中做到这一点（注意用 // <<<<<<<<<<<< Change here 标记的更改）
public class FirstInput extends AppCompatActivity {
//variables
int wordLength;
static int count = 0;
char[] lineNumbers; // <<<<<<<<<<<<<<<< Change here
Intent intent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first_input);
wordLength = getIntent().getIntExtra("length", 0); //receiving value of previous activity
lineNumbers = new char[wordLength] // <<<<<<<<<<<<<<< Change here
}
....
我是 Android 开发的新手。
我正在使用 Intent.
Activity 传递一个值（int 类型）
Intent intent = new Intent(this, NewActivity.class);
intent.putExtra("length", length); //value is taken from a edit text
startActivity(intent);
然后在 NewActivity 中，我在 onCreate() 方法中添加了这段代码。
arrayLength = getIntent().getIntExtra("length", 0); //int type arrayLength variabel is diclared globally.
然后我尝试在 NewActivity 上初始化一个数组（功能失效）为：
char[] array = new char[arrayLength];
然后我在循环中添加数组元素并尝试使用 Button 在 TextView 中显示。
但是，当我单击 Button 以使用以下代码行显示数组元素时，我的应用程序崩溃了：
arrayElemtsShow.setText(new String (array));
But if I initialize this array with a constant like below, it works fine.
char[] array = new char[20];
但重要的是使用前一个 Activity 的值初始化这个数组。
我该怎么做才能解决这个问题？
为什么会这样？
Logcat:
> 2020-06-03 08:43:41.449 30912-30912/? I/.aam.secretnam: Late-enabling
> -Xcheck:jni 2020-06-03 08:43:41.721 30912-30912/com.aam.secretname I/Perf: Connecting to perf service. 2020-06-03 08:43:41.836
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method
> Landroid/graphics/drawable/Drawable;->getOpticalInsets()Landroid/graphics/Insets;
> (light greylist, linking) 2020-06-03 08:43:41.836
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> field Landroid/graphics/Insets;->left:I (light greylist, linking)
> 2020-06-03 08:43:41.836 30912-30912/com.aam.secretname
> W/.aam.secretnam: Accessing hidden field
> Landroid/graphics/Insets;->right:I (light greylist, linking)
> 2020-06-03 08:43:41.836 30912-30912/com.aam.secretname
> W/.aam.secretnam: Accessing hidden field
> Landroid/graphics/Insets;->top:I (light greylist, linking) 2020-06-03
> 08:43:41.836 30912-30912/com.aam.secretname W/.aam.secretnam:
> Accessing hidden field Landroid/graphics/Insets;->bottom:I (light
> greylist, linking) 2020-06-03 08:43:41.970
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method
> Landroid/view/View;->computeFitSystemWindows(Landroid/graphics/Rect;Landroid/graphics/Rect;)Z
> (light greylist, reflection) 2020-06-03 08:43:41.973
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method Landroid/view/ViewGroup;->makeOptionalFitsSystemWindows()V
> (light greylist, reflection) 2020-06-03 08:43:41.986
> 30912-30912/com.aam.secretname W/.aam.secretnam: Accessing hidden
> method
> Landroid/widget/TextView;->getTextDirectionHeuristic()Landroid/text/TextDirectionHeuristic;
> (light greylist, linking) 2020-06-03 08:43:42.217
> 30912-30938/com.aam.secretname I/Adreno: QUALCOMM build
> : 4e21c4c, I21281c58c8
> Build Date : 03/01/19
> OpenGL ES Shader Compiler Version: EV031.25.03.02
> Local Branch :
> Remote Branch : refs/tags/AU_LINUX_ANDROID_LA.UM.7.5.R1.09.00.00.464.039
> Remote Branch : NONE
> Reconstruct Branch : NOTHING 2020-06-03 08:43:42.217 30912-30938/com.aam.secretname I/Adreno: Build Config
> : S L 6.0.7 AArch32 2020-06-03 08:43:42.222
> 30912-30938/com.aam.secretname I/Adreno: PFP: 0x005ff110, ME:
> 0x005ff066 2020-06-03 08:43:42.227 30912-30938/com.aam.secretname
> I/ConfigStore:
> android::hardware::configstore::V1_0::ISurfaceFlingerConfigs::hasWideColorDisplay
> retrieved: 0 2020-06-03 08:43:42.227 30912-30938/com.aam.secretname
> I/ConfigStore:
> android::hardware::configstore::V1_0::ISurfaceFlingerConfigs::hasHDRDisplay
> retrieved: 0 2020-06-03 08:43:42.227 30912-30938/com.aam.secretname
> I/OpenGLRenderer: Initialized EGL, version 1.4 2020-06-03 08:43:42.227
> 30912-30938/com.aam.secretname D/OpenGLRenderer: Swap behavior 2
> 2020-06-03 08:43:42.370 30912-30912/com.aam.secretname
> I/AssistStructure: Flattened final assist data: 2924 bytes, containing
> 1 windows, 10 views 2020-06-03 08:43:46.687
> 30912-30912/com.aam.secretname I/Timeline: Timeline:
> Activity_launch_request time:527917018 2020-06-03 08:43:46.728
> 30912-30912/com.aam.secretname W/ActivityThread:
> handleWindowVisibility: no activity for token
> android.os.BinderProxy@22a035f 2020-06-03 08:43:51.641
> 30912-30912/com.aam.secretname D/AndroidRuntime: Shutting down VM
> 2020-06-03 08:43:51.645 30912-30912/com.aam.secretname
> E/AndroidRuntime: FATAL EXCEPTION: main
> Process: com.aam.secretname, PID: 30912
> java.lang.IllegalStateException: Could not execute method for android:onClick
> at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:402)
> at android.view.View.performClick(View.java:6608)
> at android.view.View.performClickInternal(View.java:6585)
> at android.view.View.access00(View.java:785)
> at android.view.View$PerformClick.run(View.java:25919)
> at android.os.Handler.handleCallback(Handler.java:873)
> at android.os.Handler.dispatchMessage(Handler.java:99)
> at android.os.Looper.loop(Looper.java:201)
> at android.app.ActivityThread.main(ActivityThread.java:6826)
> at java.lang.reflect.Method.invoke(Native Method)
> at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
> at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
> Caused by: java.lang.reflect.InvocationTargetException
> at java.lang.reflect.Method.invoke(Native Method)
> at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:397)
> at android.view.View.performClick(View.java:6608)
> at android.view.View.performClickInternal(View.java:6585)
> at android.view.View.access00(View.java:785)
> at android.view.View$PerformClick.run(View.java:25919)
> at android.os.Handler.handleCallback(Handler.java:873)
> at android.os.Handler.dispatchMessage(Handler.java:99)
> at android.os.Looper.loop(Looper.java:201)
> at android.app.ActivityThread.main(ActivityThread.java:6826)
> at java.lang.reflect.Method.invoke(Native Method)
> at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
> at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
> Caused by: java.lang.ArrayIndexOutOfBoundsException: length=0; index=0
> at com.aam.secretname.FirstInput.getLineNumbers(FirstInput.java:71)
> at com.aam.secretname.FirstInput.line3(FirstInput.java:57)
> at java.lang.reflect.Method.invoke(Native Method)
> at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:397)
> at android.view.View.performClick(View.java:6608)
> at android.view.View.performClickInternal(View.java:6585)
> at android.view.View.access00(View.java:785)
> at android.view.View$PerformClick.run(View.java:25919)
> at android.os.Handler.handleCallback(Handler.java:873)
> at android.os.Handler.dispatchMessage(Handler.java:99)
> at android.os.Looper.loop(Looper.java:201)
> at android.app.ActivityThread.main(ActivityThread.java:6826)
> at java.lang.reflect.Method.invoke(Native Method)
> at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
> at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
第一classxml
<TextView
android:id="@+id/textView5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fontFamily="serif-monospace"
android:gravity="center"
android:padding="4dp"
android:text="@string/length"
android:textColor="#66B1F3"
android:textSize="24sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.243" />
<EditText
android:id="@+id/editText"
android:layout_width="200dp"
android:layout_height="40dp"
android:autofillHints=""
android:ems="10"
android:background="@drawable/stroke"
android:gravity="center"
android:hint="@string/Enterlength"
android:inputType="textPersonName"
android:textColor="#FFFFFF"
android:textSize="20sp"
app:layout_constraintBottom_toTopOf="@+id/button2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.497"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView5"
app:layout_constraintVertical_bias="0.122" />
<Button
android:id="@+id/button2"
android:layout_width="300dp"
android:layout_height="wrap_content"
android:layout_marginBottom="44dp"
android:onClick="nextOnClick"
android:text="@string/btnnext"
android:background="@drawable/radius_button"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.491"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="@+id/btnexample"
android:layout_width="150dp"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"
android:background="@drawable/radius_button"
android:fontFamily="serif"
android:text="@string/examplebtn"
android:visibility="invisible"
android:textAllCaps="false"
android:textSize="18sp"
android:onClick="exampleOnClick"
app:layout_constraintBottom_toTopOf="@+id/button2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.781"
app:layout_constraintStart_toStartOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
第二个classXml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/gradient_background">
<TextView
android:id="@+id/textView6"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fontFamily="sans-serif-condensed-medium"
android:gravity="center"
android:padding="4dp"
android:text="@string/instruction"
android:textColor="#2E183E"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.023" />
<Button
android:id="@+id/button3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line1"
android:text="@string/alphabet_1"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView7" />
<Button
android:id="@+id/button4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line6"
android:text="@string/alphabet_6"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button5"
app:layout_constraintVertical_bias="0.0" />
<Button
android:id="@+id/button5"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line5"
android:text="@string/alphabet_5"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button6" />
<Button
android:id="@+id/button6"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line4"
android:text="@string/alphabet_4"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button7" />
<Button
android:id="@+id/button7"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line3"
android:text="@string/alphabet_3"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button8" />
<Button
android:id="@+id/button8"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/line_button_background"
android:fontFamily="sans-serif-condensed"
android:gravity="center"
android:onClick="line2"
android:text="@string/alphabet_2"
android:textColor="@color/line_color"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/button3" />
<Button
android:id="@+id/button9"
android:layout_width="150sp"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
android:layout_marginBottom="8dp"
android:background="@drawable/radius_button"
android:onClick="nextOnClick"
android:text="@string/btnnext"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
<TextView
android:id="@+id/textView7"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="4dp"
android:background="@drawable/stroke"
android:gravity="center"
android:hint="@string/line_numbers"
android:padding="2dp"
android:textColor="#fff"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@+id/textView6" />
<Button
android:id="@+id/button10"
android:layout_width="100dp"
android:layout_height="wrap_content"
android:layout_marginStart="24dp"
android:layout_marginLeft="24dp"
android:layout_marginBottom="4dp"
android:background="@drawable/back_button"
android:onClick="reset"
android:text="@string/reset"
android:textSize="16sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="@+id/button20"
android:layout_width="150dp"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_marginRight="16dp"
android:layout_marginBottom="8dp"
android:background="@drawable/radius_button"
android:fontFamily="serif"
android:text="@string/examplebtn"
android:textAllCaps="false"
android:textSize="18sp"
app:layout_constraintBottom_toTopOf="@+id/button9"
app:layout_constraintEnd_toEndOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
第一个class
package com.aam.secretname;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class LengthActivity extends AppCompatActivity {
//variables
int length = 0;
Intent intent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_length);
}
public void nextOnClick(View view) {
getLength();
if ((length > 0) && (length < 20)) {
intent = new Intent(LengthActivity.this, FirstInput.class);
intent.putExtra("length", length); //sending value in second activity
startActivity(intent);
}
}
public void exampleOnClick(View view) {
TextView showInfo = (TextView) findViewById(R.id.textView5);
Button example = (Button) findViewById(R.id.btnexample);
showInfo.setText(R.string.example);
example.setVisibility(View.INVISIBLE);
}
private void getLength() {
try {
EditText wordLength = (EditText) findViewById(R.id.editText);
int tempLength = Integer.parseInt(wordLength.getText().toString());
if ((tempLength<20) && (tempLength>0)) {
length = tempLength;
}
else {
TextView showInfo = (TextView) findViewById(R.id.textView5);
showInfo.setTextColor(Color.RED);
if (tempLength == 0) showInfo.setText(R.string.warningOfLenthZero);
else showInfo.setText(R.string.warningOfLengthLimitation);
}
}
catch (Exception e){
TextView showInfo = (TextView) findViewById(R.id.textView5);
Button example = (Button) findViewById(R.id.btnexample);
showInfo.setTextColor(Color.RED);
showInfo.setText(R.string.instuctForGivingLength);
example.setVisibility(View.VISIBLE);
}
}
}
第二个Class
package com.aam.secretname;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
import java.util.Arrays;
public class FirstInput extends AppCompatActivity {
//variables
int wordLength;
static int count = 0;
char[] lineNumbers = new char[wordLength]; //problem
Intent intent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first_input);
wordLength = getIntent().getIntExtra("length", 0); //receiving value of previous activity
}
public void nextOnClick(View view) {
intent = new Intent(FirstInput.this, FinalInput.class);
if (lineNumbers[wordLength - 1] != '[=20=]'){
intent.putExtra("lineNumbers", new String(lineNumbers));
intent.putExtra("length", wordLength);
startActivity(intent);
}
else {
TextView warning = (TextView) findViewById(R.id.textView6);
warning.setTextColor(Color.RED);
warning.setText(R.string.instuctionForTappingOnLine);
}
}
public void reset(View view) {
count = 0;
Arrays.fill(lineNumbers, '[=20=]');
Toast.makeText(this, "Reseted", Toast.LENGTH_SHORT ).show();
TextView showLineNumbers = (TextView) findViewById(R.id.textView7);
showLineNumbers.setText("");
}
public void line1(View v){
getLineNumbers('1');
}
public void line2(View v){
getLineNumbers('2');
}
public void line3(View v){
getLineNumbers('3');
}
public void line4(View v){
getLineNumbers('4');
}
public void line5(View v){
getLineNumbers('5');
}
public void line6(View v){
getLineNumbers('6');
}
private void getLineNumbers(char line) {
if(count < wordLength){
lineNumbers[count++] = line;
TextView showLineNumbers = (TextView) findViewById(R.id.textView7);
showLineNumbers.setText(new String(lineNumbers));
}
else{
TextView showInfo = (TextView) findViewById(R.id.textView6);
showInfo.setText(R.string.completedInput);
}
}
}
您应该提供例外情况logcat；但我猜你在从 EditText
中获取值时错过了将 String 转换为 intintent.putExtra("length", Integer.parseInt(length));
UPDATE:
您的问题是您将 lineNumbers 数组初始化为具有 0 个值的成员；这是因为 java 中的默认 int 值为 0。
因此，当您使用下面的声明语句时，您正在为 lineNumbers 数组分配一个长度为 0 的值，因为 wordLength 是 s 直到 0；所以你需要做的是在你 getIntent().getIntExtra() 值之后做这个作业。
在代码中做到这一点（注意用 // <<<<<<<<<<<< Change here 标记的更改）
public class FirstInput extends AppCompatActivity {
//variables
int wordLength;
static int count = 0;
char[] lineNumbers; // <<<<<<<<<<<<<<<< Change here
Intent intent;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first_input);
wordLength = getIntent().getIntExtra("length", 0); //receiving value of previous activity
lineNumbers = new char[wordLength] // <<<<<<<<<<<<<<< Change here
}
....