android - 如何让用户分享我使用 Qt for Android 编写的应用程序中的图像

Question

我正在使用 Qt 开发 Android 应用程序。现在我要让用户分享我的应用程序中的图像。我试图创建新的 Intent:

package ir.qtips;
import android.content.Intent;
import android.net.Uri;
public class ShareActivity extends org.qtproject.qt5.android.bindings.QtActivity{
    private static ShareActivity instance;

        ShareActivity() {
            instance = this;
        }

        public void createInstagramIntent(){
            String type = "image/*";
            String captionText = "<< media caption >>";

            // Create the new Intent using the 'Send' action.
            Intent share = new Intent(Intent.ACTION_SEND);

            // Set the MIME type
            share.setType(type);

            // Add the URI and the caption to the Intent.
            share.putExtra(Intent.EXTRA_STREAM,  Uri.parse("file:///sdcard/a.jpg"));
            share.putExtra(Intent.EXTRA_TEXT, caption);

            // Broadcast the Intent.
            startActivity(Intent.createChooser(share, "Share to"));
        }

}

然后我尝试从 C++ 调用 createInstagramIntent:

#ifdef Q_OS_ANDROID
    QAndroidJniObject jni("ir/qtips/ShareActivity");
    jni.callMethod<void>("createInstagramIntent");
#endif

但它不起作用。在来自应用程序的日志中，我认为一行比其他行更重要:

 java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()

Answer 1

您不能创建 Handler Thread来自尚未调用 Looper.prepare( ) 的线程。您可以做的是创建一个 Handler 线程，如下所示使用 Looper 静态类

Handler handler = new Handler(Looper.getMainLooper());

这是一个 example project调用了 Android Text to Speech Service。您可以按照此代码来解决您的问题，因为 Text To Speech 的调用方式也应与 Share Intent

相同

显示/隐藏键盘示例，它也需要从 UI 线程调用。它可能会帮助您。

{
    public void setSuspendSleep() {
        this.runOnUiThread( new Runnable() {
            public void run() 
                {
                getWindow().addFlags( WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON );
                }        
        } );
    }

    public void setAllowSleep() {
        this.runOnUiThread( new Runnable() {
            public void run() {
                getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
                }
        } );
    }
}



------- and then in C++ ------

// getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
// getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
extern "C" void SuspendSleep( int bStopSleep )
{
    static int init;
    static jobject  WindowManager_LayoutParams_FLAG_KEEP_SCREEN_ON;

    // Attaches the current thread to the JVM. 
    jint lResult; 
    jint lFlags = 0; 

    JavaVM* lJavaVM = engine.app->activity->vm; 
    JNIEnv* lJNIEnv = engine.app->activity->env; 

    JavaVMAttachArgs lJavaVMAttachArgs; 
    lJavaVMAttachArgs.version = JNI_VERSION_1_6; 
    lJavaVMAttachArgs.name = "NativeThread"; 
    lJavaVMAttachArgs.group = NULL; 

    lResult=lJavaVM->AttachCurrentThread(&lJNIEnv, &lJavaVMAttachArgs);
    if (lResult == JNI_ERR) { 
        return; 
    } 

    // Retrieves NativeActivity. 
    jobject lNativeActivity = engine.app->activity->clazz; 
    jclass ClassNativeActivity = lJNIEnv->GetObjectClass(lNativeActivity);

    if( bStopSleep )
    {
        jmethodID MethodSetFlags = lJNIEnv->GetMethodID(      ClassNativeActivity, "setSuspendSleep", "()V");
        if( MethodSetFlags )
            lJNIEnv->CallVoidMethod( lNativeActivity,  MethodSetFlags );
    }
    else
    {
        jmethodID MethodSetFlags = lJNIEnv->GetMethodID(      ClassNativeActivity, "setAllowSleep", "()V");
        if( MethodSetFlags )
            lJNIEnv->CallVoidMethod( lNativeActivity,  MethodSetFlags );
    }



    // Finished with the JVM. 
    lJavaVM->DetachCurrentThread();
}