方向改变时 EditTexts 不工作?
EditTexts aren't working when orientation changes?
我需要重新格式化现有的 Android 应用程序以获得横向版本。当数字输入 2 个 EditText(账单金额和小费百分比)时,它使用 TextWatcher 来计算小费金额。它自己工作,但是当我添加第二个布局时,TextWatcher 停止工作并且不计算任何东西。它旋转并看起来像我想要的那样,但不起作用。我的横向布局与具有相同 EditText 和 TextView ID 的纵向布局具有所有相同的部分。这就是我用来更改布局的内容:
package com.example.tiporientation;
import androidx.appcompat.app.AppCompatActivity;
import android.content.res.Configuration;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.widget.EditText;
import android.widget.TextView;
import java.text.NumberFormat;
public class MainActivity extends AppCompatActivity {
private TipCalculator tipCalc;
private NumberFormat money = NumberFormat.getCurrencyInstance();
private EditText billEditText;
private EditText tipEditText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
tipCalc = new TipCalculator(.17f,100);
setContentView(R.layout.activity_main);
billEditText = findViewById(R.id.EDIT_BillAmount);
tipEditText = findViewById(R.id.EDIT_EnterTip);
//create inner-class for this... puts it at bottom of MainActivity
//TextChangeHandler is a "listener"
//attach it to our EDIT texts, so it is listening to changes in bill $ & tip %
TextChangeHandler tch = new TextChangeHandler();
billEditText.addTextChangedListener(tch);
tipEditText.addTextChangedListener(tch);
Configuration config = getResources().getConfiguration();
modifyLayout(config);
}
private void modifyLayout(Configuration newConfig) {
if(newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE)
setContentView(R.layout.activity_main_landscape); //we create new XML for this layout
else if(newConfig.orientation == Configuration.ORIENTATION_PORTRAIT)
setContentView(R.layout.activity_main);
}
public void onConfigurationChanged(Configuration newConfig) {
Log.w("MainActivity", "Inside onConfigurationChanged");
super.onConfigurationChanged(newConfig);
modifyLayout(newConfig); //if orientation changes again, send back to modifyLayout
}
public void calculate () {
//convert edit texts to a string ???
String billString = billEditText.getText().toString();
String tipString = tipEditText.getText().toString();
//2 text views from XML
TextView tipTextView = findViewById(R.id.TXT_TipTotal);
TextView totalTextView = findViewById(R.id.TXT_TotalAmount);
try {
//convert billString to float & tipString to int -- can't do math with strings
float billAmount = Float.parseFloat(billString);
int tipPercent = Integer.parseInt(tipString);
//update the model -- referencing TipCalculator class!
tipCalc.setBill(billAmount);
tipCalc.setTip(.01f * tipPercent);
//ask model to calculate
float tip = tipCalc.tipAmount();
float total = tipCalc.totalAmount();
//update view with formatted tip & total amount
tipTextView.setText(money.format(tip));
totalTextView.setText(money.format(total));
} catch(NumberFormatException nfe) { }
}
//create implements... select all 3 they are then stubbed out in the class
private class TextChangeHandler implements TextWatcher {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
@Override
public void afterTextChanged(Editable s) {
calculate();
}
}
}
清单:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.tiporientation">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity"
android:configChanges="orientation|screenSize">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
通过 onConfigurationChanged 回调,您的 activity 被销毁并重新创建。
文本字段中的值可以存储在 savedInstanceState
中,然后在 onCreate 中检索。
我不完全确定,但我认为这里发生的是:
- Phone轮换
- Phone 重新创建 activity(您的 onCreate 运行s)
- 您收到 onConfiguration 回调
- 你分配了一个新的 contentView(_landscape)
- 这样你就破坏了刚刚在 onCreate 和你的监听器中呈现的布局
您的 onCreate
已经 运行,因此您的 TextWatcher
已附加到您刚刚使用来自 modifyLayout
.
的 setContentView 调用破坏的布局
我仍然认为你应该让 android 为你管理这个,但为了解决这个问题,我建议:
从 onCreate 中删除代码,从第一个 findViewById 开始直到(包括).addTextWatcher 行
通过 onCreate
中的额外 modifyLayout 调用消除其他混乱
将这段代码放在一个方法中,比如 connectWatchers
从 onCreate
调用此方法
从 modifyLayout
调用此方法
它应该是这样的:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
tipCalc = new TipCalculator(.17f,100);
setContentView(R.layout.activity_main);
connectWatchers();
}
private void modifyLayout(Configuration newConfig) {
if(newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE)
setContentView(R.layout.activity_main_landscape); //we create new XML for this layout
else if(newConfig.orientation == Configuration.ORIENTATION_PORTRAIT)
setContentView(R.layout.activity_main);
connectWatchers();
}
public void onConfigurationChanged(Configuration newConfig) {
Log.w("MainActivity", "Inside onConfigurationChanged");
super.onConfigurationChanged(newConfig);
modifyLayout(newConfig); //if orientation changes again, send back to modifyLayout
}
private void connectWatchers() {
billEditText = findViewById(R.id.EDIT_BillAmount);
tipEditText = findViewById(R.id.EDIT_EnterTip);
TextChangeHandler tch = new TextChangeHandler();
billEditText.addTextChangedListener(tch);
tipEditText.addTextChangedListener(tch);
}
我需要重新格式化现有的 Android 应用程序以获得横向版本。当数字输入 2 个 EditText(账单金额和小费百分比)时,它使用 TextWatcher 来计算小费金额。它自己工作,但是当我添加第二个布局时,TextWatcher 停止工作并且不计算任何东西。它旋转并看起来像我想要的那样,但不起作用。我的横向布局与具有相同 EditText 和 TextView ID 的纵向布局具有所有相同的部分。这就是我用来更改布局的内容:
package com.example.tiporientation;
import androidx.appcompat.app.AppCompatActivity;
import android.content.res.Configuration;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.widget.EditText;
import android.widget.TextView;
import java.text.NumberFormat;
public class MainActivity extends AppCompatActivity {
private TipCalculator tipCalc;
private NumberFormat money = NumberFormat.getCurrencyInstance();
private EditText billEditText;
private EditText tipEditText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
tipCalc = new TipCalculator(.17f,100);
setContentView(R.layout.activity_main);
billEditText = findViewById(R.id.EDIT_BillAmount);
tipEditText = findViewById(R.id.EDIT_EnterTip);
//create inner-class for this... puts it at bottom of MainActivity
//TextChangeHandler is a "listener"
//attach it to our EDIT texts, so it is listening to changes in bill $ & tip %
TextChangeHandler tch = new TextChangeHandler();
billEditText.addTextChangedListener(tch);
tipEditText.addTextChangedListener(tch);
Configuration config = getResources().getConfiguration();
modifyLayout(config);
}
private void modifyLayout(Configuration newConfig) {
if(newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE)
setContentView(R.layout.activity_main_landscape); //we create new XML for this layout
else if(newConfig.orientation == Configuration.ORIENTATION_PORTRAIT)
setContentView(R.layout.activity_main);
}
public void onConfigurationChanged(Configuration newConfig) {
Log.w("MainActivity", "Inside onConfigurationChanged");
super.onConfigurationChanged(newConfig);
modifyLayout(newConfig); //if orientation changes again, send back to modifyLayout
}
public void calculate () {
//convert edit texts to a string ???
String billString = billEditText.getText().toString();
String tipString = tipEditText.getText().toString();
//2 text views from XML
TextView tipTextView = findViewById(R.id.TXT_TipTotal);
TextView totalTextView = findViewById(R.id.TXT_TotalAmount);
try {
//convert billString to float & tipString to int -- can't do math with strings
float billAmount = Float.parseFloat(billString);
int tipPercent = Integer.parseInt(tipString);
//update the model -- referencing TipCalculator class!
tipCalc.setBill(billAmount);
tipCalc.setTip(.01f * tipPercent);
//ask model to calculate
float tip = tipCalc.tipAmount();
float total = tipCalc.totalAmount();
//update view with formatted tip & total amount
tipTextView.setText(money.format(tip));
totalTextView.setText(money.format(total));
} catch(NumberFormatException nfe) { }
}
//create implements... select all 3 they are then stubbed out in the class
private class TextChangeHandler implements TextWatcher {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
@Override
public void afterTextChanged(Editable s) {
calculate();
}
}
}
清单:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.tiporientation">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity"
android:configChanges="orientation|screenSize">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
通过 onConfigurationChanged 回调,您的 activity 被销毁并重新创建。
文本字段中的值可以存储在 savedInstanceState
中,然后在 onCreate 中检索。
我不完全确定,但我认为这里发生的是:
- Phone轮换
- Phone 重新创建 activity(您的 onCreate 运行s)
- 您收到 onConfiguration 回调
- 你分配了一个新的 contentView(_landscape)
- 这样你就破坏了刚刚在 onCreate 和你的监听器中呈现的布局
您的 onCreate
已经 运行,因此您的 TextWatcher
已附加到您刚刚使用来自 modifyLayout
.
我仍然认为你应该让 android 为你管理这个,但为了解决这个问题,我建议:
从 onCreate 中删除代码,从第一个 findViewById 开始直到(包括).addTextWatcher 行
通过 onCreate
中的额外 modifyLayout 调用消除其他混乱
将这段代码放在一个方法中,比如
connectWatchers
从
onCreate
调用此方法
从
modifyLayout
调用此方法
它应该是这样的:
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
tipCalc = new TipCalculator(.17f,100);
setContentView(R.layout.activity_main);
connectWatchers();
}
private void modifyLayout(Configuration newConfig) {
if(newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE)
setContentView(R.layout.activity_main_landscape); //we create new XML for this layout
else if(newConfig.orientation == Configuration.ORIENTATION_PORTRAIT)
setContentView(R.layout.activity_main);
connectWatchers();
}
public void onConfigurationChanged(Configuration newConfig) {
Log.w("MainActivity", "Inside onConfigurationChanged");
super.onConfigurationChanged(newConfig);
modifyLayout(newConfig); //if orientation changes again, send back to modifyLayout
}
private void connectWatchers() {
billEditText = findViewById(R.id.EDIT_BillAmount);
tipEditText = findViewById(R.id.EDIT_EnterTip);
TextChangeHandler tch = new TextChangeHandler();
billEditText.addTextChangedListener(tch);
tipEditText.addTextChangedListener(tch);
}