我正在尝试使用意图开始一项活动，但它似乎永远不会起作用。我已经尝试在所有地方确定变量的范围，但它似乎从来没有工作过。我正在使用线程来启动活动。如果是因为IDE，我使用的是android studio。我只是想知道这里的错误是什么，因为我找不到。我已经包含了 Android 清单，因为我可能在那里也搞砸了。这是代码：
package com.mtprogramming.magicsquaresgame;
import com.mtprogramming.magicsquaresgame.util.SystemUiHider;
import android.annotation.TargetApi;
import android.app.Activity;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.view.MotionEvent;
import android.view.View;
/**
* An example full-screen activity that shows and hides the system UI (i.e.
* status bar and navigation/system bar) with user interaction.
*
* @see SystemUiHider
*/
public class Opening extends Activity {
/**
* Whether or not the system UI should be auto-hidden after
* {@link #AUTO_HIDE_DELAY_MILLIS} milliseconds.
*/
private static final boolean AUTO_HIDE = true;
/**
* If {@link #AUTO_HIDE} is set, the number of milliseconds to wait after
* user interaction before hiding the system UI.
*/
private static final int AUTO_HIDE_DELAY_MILLIS = 3000;
/**
* If set, will toggle the system UI visibility upon interaction. Otherwise,
* will show the system UI visibility upon interaction.
*/
private static final boolean TOGGLE_ON_CLICK = true;
/**
* The flags to pass to {@link SystemUiHider#getInstance}.
*/
private static final int HIDER_FLAGS = SystemUiHider.FLAG_HIDE_NAVIGATION;
/**
* The instance of the {@link SystemUiHider} for this activity.
*/
private SystemUiHider mSystemUiHider;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_opening);
Thread timer = new Thread(){
public void run(){
try{
sleep(5000);
}catch(Exception e){
e.printStackTrace();
}finally{
Intent open = new Intent(Opening.this,Menu.class);
startActivity(open);
}
}
};
timer.start();
final View controlsView = findViewById(R.id.fullscreen_content_controls);
final View contentView = findViewById(R.id.fullscreen_content);
// Set up an instance of SystemUiHider to control the system UI for
// this activity.
mSystemUiHider = SystemUiHider.getInstance(this, contentView, HIDER_FLAGS);
mSystemUiHider.setup();
mSystemUiHider
.setOnVisibilityChangeListener(new SystemUiHider.OnVisibilityChangeListener() {
// Cached values.
int mControlsHeight;
int mShortAnimTime;
@Override
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR2)
public void onVisibilityChange(boolean visible) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
// If the ViewPropertyAnimator API is available
// (Honeycomb MR2 and later), use it to animate the
// in-layout UI controls at the bottom of the
// screen.
if (mControlsHeight == 0) {
mControlsHeight = controlsView.getHeight();
}
if (mShortAnimTime == 0) {
mShortAnimTime = getResources().getInteger(
android.R.integer.config_shortAnimTime);
}
controlsView.animate()
.translationY(visible ? 0 : mControlsHeight)
.setDuration(mShortAnimTime);
} else {
// If the ViewPropertyAnimator APIs aren't
// available, simply show or hide the in-layout UI
// controls.
controlsView.setVisibility(visible ? View.VISIBLE : View.GONE);
}
if (visible && AUTO_HIDE) {
// Schedule a hide().
delayedHide(AUTO_HIDE_DELAY_MILLIS);
}
}
});
// Set up the user interaction to manually show or hide the system UI.
contentView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (TOGGLE_ON_CLICK) {
mSystemUiHider.toggle();
} else {
mSystemUiHider.show();
}
}
});
// Upon interacting with UI controls, delay any scheduled hide()
// operations to prevent the jarring behavior of controls going away
// while interacting with the UI.
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
// Trigger the initial hide() shortly after the activity has been
// created, to briefly hint to the user that UI controls
// are available.
delayedHide(100);
}
/**
* Touch listener to use for in-layout UI controls to delay hiding the
* system UI. This is to prevent the jarring behavior of controls going away
* while interacting with activity UI.
*/
View.OnTouchListener mDelayHideTouchListener = new View.OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
if (AUTO_HIDE) {
delayedHide(AUTO_HIDE_DELAY_MILLIS);
}
return false;
}
};
Handler mHideHandler = new Handler();
Runnable mHideRunnable = new Runnable() {
@Override
public void run() {
mSystemUiHider.hide();
}
};
/**
* Schedules a call to hide() in [delay] milliseconds, canceling any
* previously scheduled calls.
*/
private void delayedHide(int delayMillis) {
mHideHandler.removeCallbacks(mHideRunnable);
mHideHandler.postDelayed(mHideRunnable, delayMillis);
}}
和 Android 清单：
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.mtprogramming.magicsquaresgame.Opening"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="@string/app_name"
android:theme="@style/FullscreenTheme"
android:screenOrientation="landscape">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.mtprogramming.magicsquaresgame.Menu"
android:configChanges="orientation|keyboardHidden|screenSize"
android:label="@string/app_name"
android:theme="@style/FullscreenTheme"
android:screenOrientation="landscape"
>
<intent-filter> <action> android:name="com.mtprogramming.magicsquaresgame.MENU"</action>
</intent-filter>
</activity>
</application>
顺便说一下，目标 API 是 16-17。