图片未在秒内显示 activity
Image is not displaying in second activity
当我单击时,按钮库打开并且我 select 图像,但图像没有显示在第二个 Activity 中。
我从几天开始尝试,但没有得到结果。请帮我提供完整的代码。
这是我的代码:
Activity 1
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
import androidx.appcompat.app.AppCompatActivity;
public class HomepageActivity extends AppCompatActivity {
private static final int SELECT_PHOTO = 1;
private static int RESULT_LOAD_IMAGE = 1;
/**
* Called when the activity is first created.
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_homepage);
ImageButton buttonLoadImage = findViewById(R.id.btnphoto);
buttonLoadImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent gallery = new Intent(Intent.ACTION_GET_CONTENT);
gallery.setType("image/*");
startActivityForResult(gallery, RESULT_LOAD_IMAGE);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == SELECT_PHOTO) {
if (resultCode == RESULT_OK) {
Uri selectedImage = data.getData();
if (selectedImage != null) {
Intent gallery = new Intent(HomepageActivity.this, ImageActivity.class);
Bundle extras = new Bundle();
extras.putString("image", selectedImage.toString());
gallery.putExtras(extras);
startActivity(gallery);
}
}
}
}}```
Activity 2
Public class ImageActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image);
Bundle extras = getIntent().getExtras();
String name = extras.getString("image");
Uri imageFinal=Uri.parse(name);
}}```
在ImageActivity的onCreate方法中
ImageView imageView = findViewById(R.id.gallery_image);
Bundle bundle = getIntent().getExtras();
if(bundle != null) {
String uriString = bundle.getString("image");
Uri uri = Uri.parse(uriString);
try {
imageView.setImageBitmap(decodeUri(this,uri, 300));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
decodeUri 是一个示例方法(仅限工作代码),用于调整图像大小转换为位图并设置为 imageview。如果图像尺寸很大,您可能会得到 java.lang.RuntimeException: Canvas: trying to draw too large(168709632bytes) bitmap.
public static Bitmap decodeUri(Context c, Uri uri, final int requiredSize)
throws FileNotFoundException {
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(c.getContentResolver().openInputStream(uri), null, o);
int width_tmp = o.outWidth
, height_tmp = o.outHeight;
int scale = 1;
while(true) {
if(width_tmp / 2 < requiredSize || height_tmp / 2 < requiredSize)
break;
width_tmp /= 2;
height_tmp /= 2;
scale *= 2;
}
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
return BitmapFactory.decodeStream(c.getContentResolver().openInputStream(uri), null, o2);
}
activity_gallery_image.xml
<?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"
tools:context=".GalleryImageActivity">
<ImageView
android:id="@+id/gallery_image"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.5"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:srcCompat="@tools:sample/avatars" />
</androidx.constraintlayout.widget.ConstraintLayout>
更改 onActivityResult 中的 if 状态
if (requestCode == RESULT_LOAD_IMAGE)
尝试将图像转换为字节数组,然后将其传递给下一个 activity(作为 ByteArray)并使用它。
当我单击时,按钮库打开并且我 select 图像,但图像没有显示在第二个 Activity 中。 我从几天开始尝试,但没有得到结果。请帮我提供完整的代码。 这是我的代码:
Activity 1
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
import androidx.appcompat.app.AppCompatActivity;
public class HomepageActivity extends AppCompatActivity {
private static final int SELECT_PHOTO = 1;
private static int RESULT_LOAD_IMAGE = 1;
/**
* Called when the activity is first created.
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_homepage);
ImageButton buttonLoadImage = findViewById(R.id.btnphoto);
buttonLoadImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent gallery = new Intent(Intent.ACTION_GET_CONTENT);
gallery.setType("image/*");
startActivityForResult(gallery, RESULT_LOAD_IMAGE);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == SELECT_PHOTO) {
if (resultCode == RESULT_OK) {
Uri selectedImage = data.getData();
if (selectedImage != null) {
Intent gallery = new Intent(HomepageActivity.this, ImageActivity.class);
Bundle extras = new Bundle();
extras.putString("image", selectedImage.toString());
gallery.putExtras(extras);
startActivity(gallery);
}
}
}
}}```
Activity 2
Public class ImageActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image);
Bundle extras = getIntent().getExtras();
String name = extras.getString("image");
Uri imageFinal=Uri.parse(name);
}}```
在ImageActivity的onCreate方法中
ImageView imageView = findViewById(R.id.gallery_image);
Bundle bundle = getIntent().getExtras();
if(bundle != null) {
String uriString = bundle.getString("image");
Uri uri = Uri.parse(uriString);
try {
imageView.setImageBitmap(decodeUri(this,uri, 300));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
decodeUri 是一个示例方法(仅限工作代码),用于调整图像大小转换为位图并设置为 imageview。如果图像尺寸很大,您可能会得到 java.lang.RuntimeException: Canvas: trying to draw too large(168709632bytes) bitmap.
public static Bitmap decodeUri(Context c, Uri uri, final int requiredSize)
throws FileNotFoundException {
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(c.getContentResolver().openInputStream(uri), null, o);
int width_tmp = o.outWidth
, height_tmp = o.outHeight;
int scale = 1;
while(true) {
if(width_tmp / 2 < requiredSize || height_tmp / 2 < requiredSize)
break;
width_tmp /= 2;
height_tmp /= 2;
scale *= 2;
}
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
return BitmapFactory.decodeStream(c.getContentResolver().openInputStream(uri), null, o2);
}
activity_gallery_image.xml
<?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"
tools:context=".GalleryImageActivity">
<ImageView
android:id="@+id/gallery_image"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.5"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:srcCompat="@tools:sample/avatars" />
</androidx.constraintlayout.widget.ConstraintLayout>
更改 onActivityResult 中的 if 状态
if (requestCode == RESULT_LOAD_IMAGE)
尝试将图像转换为字节数组,然后将其传递给下一个 activity(作为 ByteArray)并使用它。