通常会看到点击ImageView弹出一个Dialog上面有一张大图,然后长按大图可以保存
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="16dp">
<ImageView
android:id="@+id/image"
android:src="@mipmap/ic_launcher"
android:layout_centerInParent="true"
android:layout_width="100dp"
android:layout_height="100dp" />
</RelativeLayout>
my_dialog.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:alpha="0.5">
<ImageView
android:id="@+id/my_image"
android:padding="10dp"
android:src="@mipmap/ic_launcher"
android:layout_width="300dp"
android:layout_height="300dp"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>
MainActivity.class
package visahall.cn.testsavebitmap;
import android.app.Dialog;
import android.content.DialogInterface;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.os.Bundle;
import android.support.annotation.RequiresApi;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
public class MainActivity extends AppCompatActivity {
private ImageView imageView;
private Dialog dialog;
private ImageView mImageView;
@RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
//小图的点击事件(弹出大图)
imageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
dialog.show();
}
});
}
private void init() {
imageView = (ImageView) findViewById(R.id.image);
//大图所依附的dialog
dialog = new Dialog(MainActivity.this, R.style.AlertDialog_AppCompat_Light_);
mImageView = getImageView();
dialog.setContentView(mImageView);
//大图的点击事件(点击让他消失)
mImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
dialog.dismiss();
}
});
//大图的长按监听
mImageView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
//弹出的“保存图片”的Dialog
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setItems(new String[]{getResources().getString(R.string.save_picture)}, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
saveCroppedImage(((BitmapDrawable) mImageView.getDrawable()).getBitmap());
}
});
builder.show();
return true;
}
});
}
//保存图片
private void saveCroppedImage(Bitmap bmp) {
File file = new File("/sdcard/myFolder");
if (!file.exists())
file.mkdir();
file = new File("/sdcard/temp.jpg".trim());
String fileName = file.getName();
String mName = fileName.substring(0, fileName.lastIndexOf("."));
String sName = fileName.substring(fileName.lastIndexOf("."));
// /sdcard/myFolder/temp_cropped.jpg
String newFilePath = "/sdcard/myFolder" + "/" + mName + "_cropped" + sName;
file = new File(newFilePath);
try {
file.createNewFile();
FileOutputStream fos = new FileOutputStream(file);
bmp.compress(Bitmap.CompressFormat.JPEG, 50, fos);
fos.flush();
fos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
//动态的ImageView
private ImageView getImageView(){
ImageView iv = new ImageView(this);
//宽高
iv.setLayoutParams(new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
//设置Padding
iv.setPadding(20,20,20,20);
//imageView设置图片
InputStream is = getResources().openRawResource(R.mipmap.ic_launcher);
Drawable drawable = BitmapDrawable.createFromStream(is, null);
iv.setImageDrawable(drawable);
return iv;
}
}