点击后，我的应用程序在相机和图库之间进行选择，然后该图片将显示在ImageView中。我最初试图显示完整的图像然后尝试使用位图方式但没有任何作用。我只是得到一个空白的ImageView。请给我一些关于我做错的指导，并在必要时要求澄清：
相机/图库照片代码：
Uri outputFileUri;
private void openImageIntent() {
// Determine Uri of camera image to save.
final File root = new File(Environment.getExternalStorageDirectory() + File.separator + "MyDir" + File.separator);
root.mkdirs();
final String fname = "img_" + System.currentTimeMillis() + ".jpg";
final File sdImageMainDirectory = new File(root, fname);
outputFileUri = Uri.fromFile(sdImageMainDirectory);
// Camera.
final List<Intent> cameraIntents = new ArrayList<Intent>();
final Intent captureIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
final PackageManager packageManager = getPackageManager();
final List<ResolveInfo> listCam = packageManager.queryIntentActivities(captureIntent, 0);
for(ResolveInfo res : listCam) {
final String packageName = res.activityInfo.packageName;
final Intent intent = new Intent(captureIntent);
intent.setComponent(new ComponentName(res.activityInfo.packageName, res.activityInfo.name));
intent.setPackage(packageName);
intent.putExtra(MediaStore.EXTRA_OUTPUT, outputFileUri);
cameraIntents.add(intent);
}
// Filesystem.
final Intent galleryIntent = new Intent();
galleryIntent.setType("image/*");
galleryIntent.setAction(Intent.ACTION_GET_CONTENT);
// Chooser of filesystem options.
final Intent chooserIntent = Intent.createChooser(galleryIntent, "Select Source");
// Add the camera options.
chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, cameraIntents.toArray(new Parcelable[]{}));
startActivityForResult(chooserIntent, 0);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent returnIntent) {
super.onActivityResult(resultCode, requestCode, returnIntent);
if(requestCode == 0) {
if(resultCode == RESULT_OK) {
final boolean isCamera;
if(returnIntent == null) {
isCamera = true;
}
else
{
final String action = returnIntent.getAction();
if(action == null) {
isCamera = false;
}
else {
isCamera = action.equals(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
}
}
Uri selectedImageUri;
if(isCamera) {
selectedImageUri = outputFileUri;
mainImage.setImageURI(selectedImageUri); //trying full image
}
else {
selectedImageUri = returnIntent == null ? null : returnIntent.getData();
try {
Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), selectedImageUri);
mainImage.setImageBitmap(bitmap); //trying bitmap
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
答案 0 :(得分：1)
如果您想从相机拍摄图像，可以使用此过程：
public void fromCamera(){
String path= Environment.getExternalStorageDirectory().getPath() + "/DCIM/Camera/";
File file = new File(path,"IMG_"+System.currentTimeMillis()+".jpg");
file.getParentFile().mkdirs();
try {
file.createNewFile();
}catch (IOException e) {
e.printStackTrace();
}
mPicCaptureUri = Uri.fromFile(file);
Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, mPicCaptureUri);
startActivityForResult(intent, REQUEST_CAMERA);
}
如果你想要来自画廊的图像，那么：
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(Intent.createChooser(intent, getString(R.string.select_file)), REQUEST_GALLERY);
在onActivityResult上，您可以获取所选图像的路径，并在图像视图中设置图像....
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(resultCode == RESULT_OK){
if (requestCode == REQUEST_GALLERY && data != null && data.getData() != null) {
Uri selectedImageUri = data.getData();
//do set your image here
}else if(requestCode == REQUEST_CAMERA){
if(mPicCaptureUri!=null){
//do try to set image here
}
}
}
}
不要忘记在顶部定义mPicCaptureUri：
private Uri mPicCaptureUri = null;
您可以从上面的代码中获取想法..它可能会帮助您
答案 1 :(得分：1)
您的问题是由于图像尺寸，您的ImageView无法显示图像。我像这样使用ImageView尝试这个代码
<ImageView
android:id="@+id/mainImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:src="@drawable/abc_ab_bottom_solid_dark_holo" />
如果你像这样使用高度和宽度dp
android:layout_width="100dp"
android:layout_height="100dp"
您需要压缩位图以在ImageView中显示它。 编辑您的代码以进行转换
if(isCamera) {
selectedImageUri = outputFileUri;
try {
Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), selectedImageUri);//You can use this bitmap if need full image to further use
Bitmap bitmap2 = Bitmap.createScaledBitmap(bitmap, 600 ,600, true);//this bitmap2 you can use only for display
mainImage.setImageBitmap(bitmap2); //trying full image
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
else {
selectedImageUri = returnIntent == null ? null : returnIntent.getData();
try {
Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), selectedImageUri);
bitmap = Bitmap.createScaledBitmap(bitmap, 600 ,600, true);
mainImage.setImageBitmap(bitmap); //trying bitmap
} catch (IOException e) {
e.printStackTrace();
}
}
答案 2 :(得分：0)
现在你可以使用Picasso Library：D
Picasso.with(context)
.load(item.getPhotoUri())
.resize(512,512)
.placeholder(R.drawable.noimage)
.error(R.drawable.error_image)
.into(photo);
答案 3 :(得分：0)
主要是由于图像太大，无法在运行时的那一纳秒范围内由位图渲染，因此您将看不到它。使用一个名为Glide的库。它解决了我在Android中的所有图像问题，包括在单个列表或网格中显示数百张图像时的性能。