1.activity_main.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="300dp"
android:layout_height="300dp"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:src="@drawable/ic_launcher" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="@+id/imageView1"
android:text="相册裁剪" />
</RelativeLayout>
2.在MainActivity里边写:
package com.example.crop;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
public class MainActivity extends Activity {
private ImageView imageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageView = (ImageView) findViewById(R.id.imageView1);
findViewById(R.id.button1).setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// (1)设置相册的意图(权限)
Intent intent = new Intent(Intent.ACTION_PICK);
// (2)设置显式MIME数据类型
intent.setType("image/*");
// (3)跳转回传
startActivityForResult(intent, 1);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch (requestCode) {
case 1:
// (4)从返回值中直接获取路径
Uri uri = data.getData();
Intent crop = crop(uri);
startActivityForResult(crop, 2);
break;
case 2:
Bitmap bitmap=data.getParcelableExtra("data");
imageView.setImageBitmap(bitmap);
break;
}
}
private Intent crop(Uri uri) {
/*
* 1.图片 uri
* 2.裁剪框
* 3.裁剪后的图片
*/
// 裁剪图片意图
Intent intent = new Intent("com.android.camera.action.CROP");
// 设置裁剪的数据源和数据类型
intent.setDataAndType(uri, "image/*");
// 可裁剪
intent.putExtra("crop", true);
// 裁剪框的比例,1:1
intent.putExtra("aspectX", 1);
intent.putExtra("aspectY", 1);
// 裁剪后输出图片的尺寸大小(图片展示到imageView的大小,不要太大了,不然会出错)
// 参数(1.输出的大小,大小)
intent.putExtra("outputX", 250);
intent.putExtra("outputY", 250);
// 图片格式(参数:输出格式,格式)
intent.putExtra("outputFormat", "JPEG");
// 必须加,否则返回值中找不到返回的值
intent.putExtra("return-data", true);// 若为true则表示返回数据(图片)
return intent;
}
}