关于解决 从相册中选择照片后无法剪切图片以及无法加载图片的问题

程序分析：

主要分两个部分

    （1）先拍照，然后剪切，最后显示出来。    （2）从相册中选择一张照片进行剪切然后显示出来

代码参照《第一行代码》，书中的代码运行时（2）出现了问题，无法剪切图片且无法加载图片

MainActivity.java代码如下：

  1 package com.example.lynn.choosepictest;
  2 
  3 import android.content.Intent;
  4 import android.graphics.Bitmap;
  5 import android.graphics.BitmapFactory;
  6 import android.net.Uri;
  7 import android.os.Environment;
  8 import android.provider.MediaStore;
  9 import android.support.v7.app.AppCompatActivity;
 10 import android.os.Bundle;
 11 import android.util.Log;
 12 import android.view.View;
 13 import android.widget.Button;
 14 import android.widget.ImageView;
 15 
 16 import java.io.File;
 17 import java.io.FileNotFoundException;
 18 
 19 public class MainActivity extends AppCompatActivity {
 20 
 21     public static final int TAKE_PHOTO = 1;
 22     public static final int CROP_PHOTO = 2;
 23     private Button takePic;
 24     private Button chooseBtn;
 25     private ImageView picture;
 26     private Uri imageUri;
 27 
 28     @Override
 29     protected void onCreate(Bundle savedInstanceState) {
 30         super.onCreate(savedInstanceState);
 31         setContentView(R.layout.activity_main);
 32         takePic = (Button) findViewById(R.id.take_pic);
 33         chooseBtn = (Button) findViewById(R.id.choose_from_album);
 34 
 35         chooseBtn.setOnClickListener(new View.OnClickListener() {
 36             @Override
 37             public void onClick(View v) {
 38                 File outputImage = new File(Environment.getExternalStorageDirectory()
 39                         , "output_Image.jpg");
 40                 try {
 41                     if (outputImage.exists()) {
 42                         outputImage.delete();
 43                     }
 44                     outputImage.createNewFile();
 45                 } catch (Exception e) {
 46                     e.printStackTrace();
 47                 }
 48 
 49                 imageUri = Uri.fromFile(outputImage);
 50                 Intent intent = new Intent("android.intent.action.PICK");
 51                 intent.setType("image/*");
 52                 intent.putExtra("crop", true);
 53                 intent.putExtra("scale", true);
 54                // intent.putExtra(MediaStore.EXTRA_OUTPUT,imageUri);
 55                              //   书中的这个代码没有运行，说明选中图片imageUri没有传过去，或者说就是空的！
 56                 startActivityForResult(intent, TAKE_PHOTO);//参数传TAKE_PHOTO
 57             }
 58         });
 59 
 60         takePic.setOnClickListener(new View.OnClickListener() {
 61             @Override
 62             public void onClick(View v) {
 63 
 64                 File outputImage = new File(Environment.getExternalStorageDirectory(), "tempImage.jpg");
 65                 try {
 66                     if (outputImage.exists()) {
 67                         outputImage.delete();
 68                     }
 69                     outputImage.createNewFile();
 70                 } catch (Exception e) {
 71                     e.printStackTrace();
 72                 }
 73                 imageUri = Uri.fromFile(outputImage);
 74                 Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
 75                 intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
 76                 startActivityForResult(intent, TAKE_PHOTO);//启动相机程序
 77 
 78             }
 79         });
 80     }
 81 
 82     @Override
 83     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
 84 
 85         switch (requestCode) {
 86             //裁剪工作
 87             case TAKE_PHOTO:
 88               
 89                 if (resultCode == RESULT_OK) {
 90                     if(data != null) {
 91                         imageUri = data.getData();  //此句是关键  在选中图片后imageUri并没有取到值，所以在这取值
 92                    }      
 93                     Log.e("TAG","TAKE_PHOTO");
 94                     Intent intent1 = new Intent("com.android.camera.action.CROP");
 95                     intent1.setDataAndType(imageUri, "image/*");
 96                     intent1.putExtra("scale", true);
 97                     intent1.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
 98                     startActivityForResult(intent1, CROP_PHOTO);
 99                 }
100                 break;
101 
102             
103             //显示图片
104             case CROP_PHOTO:
105                 if (resultCode == RESULT_OK) {
106                     try {
107                         Bitmap bitmap = BitmapFactory.decodeStream(
108                                 getContentResolver()
109                                         .openInputStream(imageUri));
110                         picture.setImageBitmap(bitmap);
111                     } catch (FileNotFoundException e) {
112                         e.printStackTrace();
113                     }
114                 }
115                 break;
116             default:
117                 break;
118         }
119     }
120 }

View Code

 

转载于:https://www.cnblogs.com/Lynn0814/p/5329432.html