報錯如下：

E/AndroidRuntime: FATAL EXCEPTION: mainProcess: com.gxuwz.yixin, PID: 29723java.lang.RuntimeException: Unable to start activity ComponentInfo{com.gxuwz.yixin/com.gxuwz.yixin.activity.edit.EditAddressActivity}: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running?at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3315)at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3464)at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2051)at android.os.Handler.dispatchMessage(Handler.java:107)at android.os.Looper.loop(Looper.java:239)at android.app.ActivityThread.main(ActivityThread.java:7604)at java.lang.reflect.Method.invoke(Native Method)at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539)at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:953)Caused by: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running?at android.view.ViewRootImpl.setView(ViewRootImpl.java:989)at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:387)at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:97)at android.widget.PopupWindow.originalInvokePopup(PopupWindow.java:1590)at android.widget.PopupWindow.invokePopup(PopupWindow.java:1575)at android.widget.PopupWindow.showAtLocation(PopupWindow.java:1345)at android.widget.PopupWindow.showAtLocation(PopupWindow.java:1311)at com.gxuwz.yixin.activity.edit.EditAddressActivity.onCreate(EditAddressActivity.java:46)at android.app.Activity.performCreate(Activity.java:7916)at android.app.Activity.performCreate(Activity.java:7903)at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1306)at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3290)at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3464) at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2051) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:239) at android.app.ActivityThread.main(ActivityThread.java:7604) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:953)

主要就這句：Unable to add window -- token null is not valid; is your activity running?

最終的意思就是，你的 Activity 視圖還沒有加載完，你就要在此 Activity 上添加對話框是不可以的
因為每一個對話框都要依附于一個 Activity，所以我們要用到一個判斷 Activity 加載完的方法，在 Activity 加載完畢之后調用對話框即可

@Overridepublic void onWindowFocusChanged(boolean hasFocus){if (hasFocus) {// 調用對話框部分}}

但是有的小伙伴會發現，這個對話框會一直跳出，點了關閉又跳出，重復執行，所以我加了個計數器來判斷。

int count = 0; @Overridepublic void onWindowFocusChanged(boolean hasFocus){if (hasFocus && count == 0) {count++;// 調用對話框部分}}

這樣一來，只有第一次進入的時候會顯示對話框，其余的時候都不會彈出了

總結

以上是生活随笔為你收集整理的Android --- 刚刚进入 Activity 页面的时候无法打开对话框，报错 Unable to add window -- token null is not valid； is your的全部內容，希望文章能夠幫你解決所遇到的問題。

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