Question

我正在构建一个应用程序，我需要从库中选择图片或通过相机拍摄新图片。我建立了三个活动：一个活动显示选定/拍摄的图片，一个活动选择从内存中选择图片作为图库，一个活动用相机拍摄新照片。我所做的是：当用户点击一个按钮获取更多图片时，我打开一个这样的意图选择器：

Intent galleryIntent = new Intent(Constants.INTENT_GALLERY);
Intent cameraIntent  = new Intent(Constants.INTENT_PHOTO_CAPTURE);

Intent chooserIntent 
            = Intent.createChooser(galleryIntent, getString(R.string.title_photo_chooser));
chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, new Intent[] { cameraIntent });

startActivityForResult(chooserIntent, Constants.SUCCESS);

然后画廊和相机活动完成如下：

Intent intent = new Intent();

intent.putStringArrayListExtra(Constants.INTENT_KEY_PHOTO, selected);

setResult(RESULT_OK, intent);
finish();

最后，第一个活动，观众，得到如下结果：

public void onActivityResult(int requestCode, int resultCode, Intent intent) {
    if (resultCode == RESULT_OK){
        if( requestCode == Constants.SUCCESS ) {
            [...]
        }
    }
}

我的手机使用API 22已经证明这是成功的。不幸的是，在使用API 16的平板电脑上运行时，在onActivityResult()中，resultCode永远不会是RESULT_OK，{{1总是 null 。我见过许多解决方案，如调用intent，但似乎没有任何效果。

任何提示都会有用。感谢。

修改

我已经用调试器分析了两个版本中我的活动内容。这些状态是调用getParent().setResult()之前Gallery活动的状态。在API 22上，我有这个：

finish()

在API 16上，我有这个：

mParent = null
mResultCode = -1
mResultData = {Intent@5081} "Intent { (has extras) }"
    mAction = null
    mCategories = null
    mClipData = null
    mComponent = null
    mContentUserHint = -2
    mData = null
    mExtras = {Bundle@5134} "Bundle[{photo=[/storage/emulated/0/DCIM/Camera/....jpg, ...]}]"
    mFlags = 0
    mLaunchParams = {DualScreenLaunchParams@5135} "DualScreenLaunchParams { mScreen=UNKNOWN mFlags=0 }"
    mMultiWindowStyle = null
    mPackage = null
    mSelector = null
    mSourceBounds = null
    mType = null
    mWindowMode = 0
    mWindowPosition = null
    mWindowScale = 0.0
    shadow$_klass_ = {Class@1261} "class android.content.Intent"
    shadow$_monitor_ = -1875875432

存在差异，但似乎mParent = null mResultCode = -1 mResultData = {Intent@830041848224} "Intent { (has extras) }" mAction = null mCategories = null mClipData = null mComponent = null mData = null mExtras = {Bundle@830042231640} "Bundle[{photo=[/storage/sdcard0/Pictures/....jpeg, ...]}]" mType = null mPackage = null mSelector = null mSourceBounds = null mFlags = 0完成了它的工作。

Answer 1

Finally, I got to the problem. The key was in the doc for startActivityForResult. It states:

For example, if the activity you are launching uses the singleTask launch mode, it will not run in your task and thus you will immediately receive a cancel result.

I was indeed using singleTask as a launch mode. I switched to singleTop and it worked. I am studying launch modes to have everything working out.

Answer 2

确保在setResult

之前未调用finish()

setContent（）用于完成不在API 16

2 个答案: