如何在本机活动上显示软键盘

时间:2011-05-03 03:41:06

标签: java android android-softkeyboard

当我尝试使用ANativeActivity_showSoftInput()时,它不会调出软键盘。

我尝试使用ANativeActivity_showSoftInput(engine->app->activity, ANATIVEACTIVITY_SHOW_SOFT_INPUT_FORCED)ANativeActivity_showSoftInput(engine->app->activity, ANATIVEACTIVITY_SHOW_SOFT_INPUT_IMPLICIT)来显示softinput,但也失败了。

我阅读了源代码,并且在开始nativeActivity后发现,NativeContentView(extend View)将被创建,当调用ANativeActivity_showSoftInput时,它将在java端调用showSoftInput()。我想也许软键盘没有打开。

你能帮助我吗?

3 个答案:

答案 0 :(得分:4)

我有完全相同的问题。无法使用此API显示键盘。

我发现的唯一方法是使用JNI,但我当然不满意这个解决方案:

android_app* mApplication;

...

void displayKeyboard(bool pShow) {
    // Attaches the current thread to the JVM.
    jint lResult;
    jint lFlags = 0;

    JavaVM* lJavaVM = mApplication->activity->vm;
    JNIEnv* lJNIEnv = mApplication->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 = mApplication->activity->clazz;
    jclass ClassNativeActivity = lJNIEnv->GetObjectClass(lNativeActivity);

    // Retrieves Context.INPUT_METHOD_SERVICE.
    jclass ClassContext = lJNIEnv->FindClass("android/content/Context");
    jfieldID FieldINPUT_METHOD_SERVICE =
        lJNIEnv->GetStaticFieldID(ClassContext,
            "INPUT_METHOD_SERVICE", "Ljava/lang/String;");
    jobject INPUT_METHOD_SERVICE =
        lJNIEnv->GetStaticObjectField(ClassContext,
            FieldINPUT_METHOD_SERVICE);
    jniCheck(INPUT_METHOD_SERVICE);

    // Runs getSystemService(Context.INPUT_METHOD_SERVICE).
    jclass ClassInputMethodManager = lJNIEnv->FindClass(
        "android/view/inputmethod/InputMethodManager");
    jmethodID MethodGetSystemService = lJNIEnv->GetMethodID(
        ClassNativeActivity, "getSystemService",
        "(Ljava/lang/String;)Ljava/lang/Object;");
    jobject lInputMethodManager = lJNIEnv->CallObjectMethod(
        lNativeActivity, MethodGetSystemService,
        INPUT_METHOD_SERVICE);

    // Runs getWindow().getDecorView().
    jmethodID MethodGetWindow = lJNIEnv->GetMethodID(
        ClassNativeActivity, "getWindow",
        "()Landroid/view/Window;");
    jobject lWindow = lJNIEnv->CallObjectMethod(lNativeActivity,
        MethodGetWindow);
    jclass ClassWindow = lJNIEnv->FindClass(
        "android/view/Window");
    jmethodID MethodGetDecorView = lJNIEnv->GetMethodID(
        ClassWindow, "getDecorView", "()Landroid/view/View;");
    jobject lDecorView = lJNIEnv->CallObjectMethod(lWindow,
        MethodGetDecorView);

    if (pShow) {
        // Runs lInputMethodManager.showSoftInput(...).
        jmethodID MethodShowSoftInput = lJNIEnv->GetMethodID(
            ClassInputMethodManager, "showSoftInput",
            "(Landroid/view/View;I)Z");
        jboolean lResult = lJNIEnv->CallBooleanMethod(
            lInputMethodManager, MethodShowSoftInput,
            lDecorView, lFlags);
    } else {
        // Runs lWindow.getViewToken()
        jclass ClassView = lJNIEnv->FindClass(
            "android/view/View");
        jmethodID MethodGetWindowToken = lJNIEnv->GetMethodID(
            ClassView, "getWindowToken", "()Landroid/os/IBinder;");
        jobject lBinder = lJNIEnv->CallObjectMethod(lDecorView,
            MethodGetWindowToken);

        // lInputMethodManager.hideSoftInput(...).
        jmethodID MethodHideSoftInput = lJNIEnv->GetMethodID(
            ClassInputMethodManager, "hideSoftInputFromWindow",
            "(Landroid/os/IBinder;I)Z");
        jboolean lRes = lJNIEnv->CallBooleanMethod(
            lInputMethodManager, MethodHideSoftInput,
            lBinder, lFlags);
    }

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

答案 1 :(得分:1)

另一种方法是使用混合解决方案,在Java中扩展NativeActivity并使用辅助函数来显示和隐藏键盘。

import android.view.inputmethod.InputMethodManager;
import android.content.Context;

public class MyNativeActivity extends android.app.NativeActivity
{
    public void showKeyboard()
    {
        InputMethodManager imm = ( InputMethodManager )getSystemService( Context.INPUT_METHOD_SERVICE );
        imm.showSoftInput( this.getWindow().getDecorView(), InputMethodManager.SHOW_FORCED );
    }

    public void hideKeyboard()
    {
        InputMethodManager imm = ( InputMethodManager )getSystemService( Context.INPUT_METHOD_SERVICE );
        imm.hideSoftInputFromWindow( this.getWindow().getDecorView().getWindowToken(), 0 );
    }
}

在原住民方面......

void DisplayKeyboard( bool bShow )
{
    // Attaches the current thread to the JVM.
    JavaVM* pJavaVM = m_pNativeActivity->vm;
    JNIEnv* pJNIEnv = m_pNativeActivity->env;

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

    jint nResult = pJavaVM->AttachCurrentThread( &pJNIEnv, &javaVMAttachArgs );
    if ( nResult != JNI_ERR ) 
    {
        // Retrieves NativeActivity.
        jobject nativeActivity = m_pNativeActivity->clazz;
        jclass ClassNativeActivity = pJNIEnv->GetObjectClass( nativeActivity );

        if ( bShow )
        {
            jmethodID MethodShowKeyboard = pJNIEnv->GetMethodID( ClassNativeActivity, "showKeyboard", "()V" );
            pJNIEnv->CallVoidMethod( nativeActivity, MethodShowKeyboard );
        }
        else
        {
            jmethodID MethodHideKeyboard = pJNIEnv->GetMethodID( ClassNativeActivity, "hideKeyboard", "()V" );
            pJNIEnv->CallVoidMethod( nativeActivity, MethodHideKeyboard );
        }

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

这允许您按原样处理Java中特定于Android的东西,并将本机代码调用到包装器中,从而降低了本机语法的复杂性。

答案 2 :(得分:0)

当视图发生变化时,我在尝试关闭软键盘时遇到了很多麻烦,直到我意识到我必须从调用它的视图中删除它:

InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
            imm.hideSoftInputFromWindow(editText.getWindowToken(), 0);

还有一个showSoftInput方法应该可以工作(假设它按照方法名称所做的那样)以类似的方式,它需要一个视图来锚定自己:

InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
            imm.showSoftInput(editText.getWindowToken(), 0);

此刻我自己无法对此进行真正的测试,但我认为它可以帮助你并且值得一试。只需确保" editText"链接到您想要接收输入的EditText。