很抱歉这不是技术问题。
我正在研究如何在Android应用程序中实现一个非常常见的功能，用户可以在其中裁剪图像的一部分。这通常使用悬停在阴影图像上方的方形窗口来执行。一个很好的例子是在linkedin应用程序中选择配置文件图像。 有谁知道或有很好的例子如何做到这一点？
提前致谢。
答案 0 :(得分：5)
试试这个：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="camera.test.demo"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="8" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:name=".SimpleCameraGalleryDemo"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
<强> 2。活动代码：
-
package camera.test.demo;
import android.app.Activity;
import android.content.ActivityNotFoundException;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
public class SimpleCameraGalleryDemo extends Activity {
private static final int PICK_FROM_CAMERA = 1;
private static final int PICK_FROM_GALLERY = 2;
ImageView imgview;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
imgview = (ImageView) findViewById(R.id.imageView1);
Button buttonCamera = (Button) findViewById(R.id.btn_take_camera);
Button buttonGallery = (Button) findViewById(R.id.btn_select_gallery);
buttonCamera.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// call android default camera
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT,
MediaStore.Images.Media.EXTERNAL_CONTENT_URI.toString());
// ******** code for crop image
intent.putExtra("crop", "true");
intent.putExtra("aspectX", 0);
intent.putExtra("aspectY", 0);
intent.putExtra("outputX", 200);
intent.putExtra("outputY", 150);
try {
intent.putExtra("return-data", true);
startActivityForResult(intent, PICK_FROM_CAMERA);
} catch (ActivityNotFoundException e) {
// Do nothing for now
}
}
});
buttonGallery.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent();
// call android default gallery
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
// ******** code for crop image
intent.putExtra("crop", "true");
intent.putExtra("aspectX", 0);
intent.putExtra("aspectY", 0);
intent.putExtra("outputX", 200);
intent.putExtra("outputY", 150);
try {
intent.putExtra("return-data", true);
startActivityForResult(Intent.createChooser(intent,
"Complete action using"), PICK_FROM_GALLERY);
} catch (ActivityNotFoundException e) {
// Do nothing for now
}
}
});
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == PICK_FROM_CAMERA) {
Bundle extras = data.getExtras();
if (extras != null) {
Bitmap photo = extras.getParcelable("data");
imgview.setImageBitmap(photo);
}
}
if (requestCode == PICK_FROM_GALLERY) {
Bundle extras2 = data.getExtras();
if (extras2 != null) {
Bitmap photo = extras2.getParcelable("data");
imgview.setImageBitmap(photo);
}
}
}
}
第3。 main.xml中
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textViewAddCard"
android:layout_width="250dp"
android:layout_height="50dp"
android:text="Take Image"
android:textSize="16dp"
android:layout_gravity="center"
android:gravity="center"
android:typeface="sans"/>
<Button
android:id="@+id/btn_take_camera"
android:layout_width="250dp"
android:layout_height="50dp"
android:text="Take From Camera"
android:layout_marginTop="5dp"
android:layout_gravity="center"
android:typeface="sans"/>
<Button
android:id="@+id/btn_select_gallery"
android:layout_width="250dp"
android:layout_height="50dp"
android:text="Select from Gallery"
android:layout_marginTop="10dp"
android:layout_gravity="center"
android:typeface="sans" />
<ImageView
android:id="@+id/imageView1"
android:layout_gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
答案 1 :(得分：5)
尝试下面的示例方法。您不仅可以从所需位图中的任何位置剪切矩形，还可以 ANY SHAPE 。
您也可以从位图中心剪切 Micky鼠标。
以下方法是切割矩形位图，使其在位图左侧具有尖三角形。像whatsapp那样可以在聊天中分享图像的缩略图。
使用 setXfermode（新的PoterDuffXfermode（Mode.CLEAR））从Paint绘制的任何内容都将清除位图中的像素。
尝试一下..希望这会有所帮助：）
private Bitmap cropAndGivePointedShape(Bitmap originalBitmap)
{
Bitmap bmOverlay = Bitmap.createBitmap(originalBitmap.getWidth(),
originalBitmap.getHeight(),
Bitmap.Config.ARGB_8888);
Paint p = new Paint();
p.setXfermode(new PorterDuffXfermode(Mode.CLEAR));
Canvas canvas = new Canvas(bmOverlay);
canvas.drawBitmap(originalBitmap, 0, 0, null);
canvas.drawRect(0, 0, 20, 20, p);
Point a = new Point(0, 20);
Point b = new Point(20, 20);
Point c = new Point(0, 40);
Path path = new Path();
path.setFillType(FillType.EVEN_ODD);
path.lineTo(b.x, b.y);
path.lineTo(c.x, c.y);
path.lineTo(a.x, a.y);
path.close();
canvas.drawPath(path, p);
a = new Point(0, 40);
b = new Point(0, 60);
c = new Point(20, 60);
path = new Path();
path.setFillType(FillType.EVEN_ODD);
path.lineTo(b.x, b.y);
path.lineTo(c.x, c.y);
path.lineTo(a.x, a.y);
path.close();
canvas.drawPath(path, p);
canvas.drawRect(0, 60, 20, originalBitmap.getHeight(), p);
return bmOverlay;
}
答案 2 :(得分：1)
试试这个库：
https://github.com/biokys/cropimage
对于一个广场：
intent.putExtra(CropImage.ASPECT_X, 2);
intent.putExtra(CropImage.ASPECT_Y, 2);
对于矩形：
intent.putExtra(CropImage.ASPECT_X, 3);
intent.putExtra(CropImage.ASPECT_Y, 2);