Android [应用代码] 简单调用系统的图片裁剪功能

截图这功能有时候很有必要，例如头像的圆角处理，不同长宽的图片，圆角处理后圆角的幅度不一样，唯有统一所有头像图片的长宽，不统一也行，那就要经过很多判断和计算（我活这么大了还没见过腾讯qq上传头像不裁剪处理的）！

应该都能看得懂了，关键的我都注释了，布局我就不贴出来了，就一个Button和一个ImageView

package com.example.screenshot;

import java.io.File;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ListAdapter;

public class MainActivity extends Activity implements OnClickListener{
Button cutBtn;
ImageView imageView;


@Override
protected void onCreate(Bundle savedInstanceState) {
super .onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cutBtn=(Button)findViewById(R.id.cutBtn);
imageView=(ImageView)findViewById(R.id.myImage);
cutBtn.setOnClickListener( this );
}


@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.cutBtn:
AlertDialog dialog;
String[] items = { "本地相册" , "相机" };
ListAdapter itemlist = new ArrayAdapter<String>( this ,
android.R.layout.simple_dropdown_item_1line, items);
AlertDialog.Builder builder = new AlertDialog.Builder( this );
builder.setAdapter(itemlist, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int item) {
if (item == 0 ) {
Intent intent = new Intent();
intent.setType( "image/*" );
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(intent, 100 );
} else {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, 101 );
}
}
});
dialog = builder.create();
dialog.show();
break ;

default :
break ;
}
}


@Override
protected void onActivityResult( int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case 100 :
startPhotoZoom(data.getData());
break ;
case 101 :
startPhotoZoom(data.getData());
break ;
case 102 :
if (data != null ){
Uri uri= Uri.parse(data.getAction());
Cursor cursor = this .getContentResolver().query(uri, null ,
null , null , null );
cursor.moveToFirst();
String path = cursor.getString( 1 );
Bitmap bitmap= new BitmapFactory().decodeFile(path);
imageView.setImageBitmap(bitmap);
}
break ;
default :
break ;
}
}


/**
* 裁剪图片方法实现
* @param uri
*/
public void startPhotoZoom(Uri uri) {
Intent intent = new Intent( "com.android.camera.action.CROP" );
intent.setDataAndType(uri, "image/*" );
//下面这个crop=true是设置在开启的Intent中设置显示的VIEW可裁剪
intent.putExtra( "crop" , "true" );
// aspectX aspectY 是宽高的比例
intent.putExtra( "aspectX" , 1 );
intent.putExtra( "aspectY" , 1 );
// outputX outputY 是裁剪图片宽高
intent.putExtra( "outputX" , 150 );
intent.putExtra( "outputY" , 150 );
startActivityForResult(intent, 102 );
}




}