调用相册并设置背景

 Button  button;
    ImageView imageView;
    //调用系统相册-选择图片
    private static final int IMAGE = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button= (Button) findViewById(R.id.but);
        imageView=(ImageView)findViewById(R.id.imageView);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                startActivityForResult(intent, IMAGE);

            }
        });

    }


    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        //获取图片路径
        if (requestCode == IMAGE && resultCode == Activity.RESULT_OK && data != null) {
            Uri selectedImage = data.getData();
            String[] filePathColumns = {MediaStore.Images.Media.DATA};
            Cursor c = getContentResolver().query(selectedImage, filePathColumns, null, null, null);
            c.moveToFirst();
            int columnIndex = c.getColumnIndex(filePathColumns[0]);
            String imagePath = c.getString(columnIndex);
            showImage(imagePath);
            c.close();
        }
    }

    //加载图片
    private void showImage(String imaePath){
        Bitmap bm = BitmapFactory.decodeFile(imaePath);
       imageView.setImageBitmap(bm);
    }


}