Android取消Toast当退出应用程序，当吐司正在显示
我已经阅读了这方面的问题，但答案似乎并不奏效。
当用户点击一个button时，我会显示一个Toast 。 当用户连续单击button时，即使用户退出活动，吐司仍会一再显示。
吐司的长度很短。 文本的长度不能改变。
这是我现在试过的：
Toast toast; toast=Toast.makeText(getApplicationContext(),"text",Toast.LENGTH_SHORT); if(toast.getView().isShown()==false){ toast.show(); }
这没有奏效。
我试过了 ：
if(toast.getView().isShown()==true){ toast.cancel(); }
在onStop() 。 由于某些原因，取消方法从不起作用。
如果我在显示应用程序之前放置.cancel() ，那么会有另一个空的检查。 但是这样做之后也不起作用。 我可以显示一个对话框而不是吐司，但这不是一个解决scheme。
有没有办法检查是否显示吐司？
以供参考
-
在Android中Toast消息
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如果有一个吐司已经显示，如何避免吐司
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如何防止多重吐司重叠
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在Android中取消已经打开的Toast
诀窍是跟踪显示的最后一个Toast ，并取消该Toast 。
我所做的就是创build一个Toast包装器，它包含了最后Toast显示的静态引用。
当我需要显示一个新的，我首先取消静态引用，之前显示新的（并保存在静态）。
这是我制作的Boast包装的完整代码 – 它足够模仿Toast方法，供我使用。 默认情况下， Boast将取消前一个，所以你不会build立一个等待显示的Toasts队列。
这个代码可以在我的Github中find：
- mobiRic /夸
如果您只是想知道如何在退出应用程序时取消通知，那么您会在该处find很多帮助。 如果您有任何改进或build议，请随时将其分叉并联系。 这是一个非常古老的答案，但代码在一些应用程序的生产中已经稳定了一段时间。
顺便说一句 – 这应该是在大多数使用情况下Toast的直接替代品 。
package mobi.glowworm.lib.ui.widget; import android.annotation.SuppressLint; import android.content.Context; import android.content.res.Resources; import android.support.annotation.Nullable; import android.widget.Toast; import java.lang.ref.WeakReference; /** * {@link Toast} decorator allowing for easy cancellation of notifications. Use this class if you * want subsequent Toast notifications to overwrite current ones. </p> * <p/> * By default, a current {@link Boast} notification will be cancelled by a subsequent notification. * This default behaviour can be changed by calling certain methods like {@link #show(boolean)}. */ public class Boast { /** * Keeps track of certain Boast notifications that may need to be cancelled. This functionality * is only offered by some of the methods in this class. * <p> * Uses a {@link WeakReference} to avoid leaking the activity context used to show the original {@link Toast}. */ @Nullable private volatile static WeakReference<Boast> weakBoast = null; @Nullable private static Boast getGlobalBoast() { if (weakBoast == null) { return null; } return weakBoast.get(); } private static void setGlobalBoast(@Nullable Boast globalBoast) { Boast.weakBoast = new WeakReference<>(globalBoast); } // //////////////////////////////////////////////////////////////////////////////////////////////////////// /** * Internal reference to the {@link Toast} object that will be displayed. */ private Toast internalToast; // //////////////////////////////////////////////////////////////////////////////////////////////////////// /** * Private constructor creates a new {@link Boast} from a given {@link Toast}. * * @throws NullPointerException if the parameter is <code>null</code>. */ private Boast(Toast toast) { // null check if (toast == null) { throw new NullPointerException("Boast.Boast(Toast) requires a non-null parameter."); } internalToast = toast; } // //////////////////////////////////////////////////////////////////////////////////////////////////////// /** * Make a standard {@link Boast} that just contains a text view. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param text The text to show. Can be formatted text. * @param duration How long to display the message. Either {@link Toast#LENGTH_SHORT} or * {@link Toast#LENGTH_LONG} */ @SuppressLint("ShowToast") public static Boast makeText(Context context, CharSequence text, int duration) { return new Boast(Toast.makeText(context, text, duration)); } /** * Make a standard {@link Boast} that just contains a text view with the text from a resource. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param resId The resource id of the string resource to use. Can be formatted text. * @param duration How long to display the message. Either {@link Toast#LENGTH_SHORT} or * {@link Toast#LENGTH_LONG} * @throws Resources.NotFoundException if the resource can't be found. */ @SuppressLint("ShowToast") public static Boast makeText(Context context, int resId, int duration) throws Resources.NotFoundException { return new Boast(Toast.makeText(context, resId, duration)); } /** * Make a standard {@link Boast} that just contains a text view. Duration defaults to * {@link Toast#LENGTH_SHORT}. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param text The text to show. Can be formatted text. */ @SuppressLint("ShowToast") public static Boast makeText(Context context, CharSequence text) { return new Boast(Toast.makeText(context, text, Toast.LENGTH_SHORT)); } /** * Make a standard {@link Boast} that just contains a text view with the text from a resource. * Duration defaults to {@link Toast#LENGTH_SHORT}. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param resId The resource id of the string resource to use. Can be formatted text. * @throws Resources.NotFoundException if the resource can't be found. */ @SuppressLint("ShowToast") public static Boast makeText(Context context, int resId) throws Resources.NotFoundException { return new Boast(Toast.makeText(context, resId, Toast.LENGTH_SHORT)); } // //////////////////////////////////////////////////////////////////////////////////////////////////////// /** * Show a standard {@link Boast} that just contains a text view. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param text The text to show. Can be formatted text. * @param duration How long to display the message. Either {@link Toast#LENGTH_SHORT} or * {@link Toast#LENGTH_LONG} */ public static void showText(Context context, CharSequence text, int duration) { Boast.makeText(context, text, duration).show(); } /** * Show a standard {@link Boast} that just contains a text view with the text from a resource. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param resId The resource id of the string resource to use. Can be formatted text. * @param duration How long to display the message. Either {@link Toast#LENGTH_SHORT} or * {@link Toast#LENGTH_LONG} * @throws Resources.NotFoundException if the resource can't be found. */ public static void showText(Context context, int resId, int duration) throws Resources.NotFoundException { Boast.makeText(context, resId, duration).show(); } /** * Show a standard {@link Boast} that just contains a text view. Duration defaults to * {@link Toast#LENGTH_SHORT}. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param text The text to show. Can be formatted text. */ public static void showText(Context context, CharSequence text) { Boast.makeText(context, text, Toast.LENGTH_SHORT).show(); } /** * Show a standard {@link Boast} that just contains a text view with the text from a resource. * Duration defaults to {@link Toast#LENGTH_SHORT}. * * @param context The context to use. Usually your {@link android.app.Application} or * {@link android.app.Activity} object. * @param resId The resource id of the string resource to use. Can be formatted text. * @throws Resources.NotFoundException if the resource can't be found. */ public static void showText(Context context, int resId) throws Resources.NotFoundException { Boast.makeText(context, resId, Toast.LENGTH_SHORT).show(); } // //////////////////////////////////////////////////////////////////////////////////////////////////////// /** * Close the view if it's showing, or don't show it if it isn't showing yet. You do not normally * have to call this. Normally view will disappear on its own after the appropriate duration. */ public void cancel() { internalToast.cancel(); } /** * Show the view for the specified duration. By default, this method cancels any current * notification to immediately display the new one. For conventional {@link Toast#show()} * queueing behaviour, use method {@link #show(boolean)}. * * @see #show(boolean) */ public void show() { show(true); } /** * Show the view for the specified duration. This method can be used to cancel the current * notification, or to queue up notifications. * * @param cancelCurrent <code>true</code> to cancel any current notification and replace it with this new * one * @see #show() */ public void show(boolean cancelCurrent) { // cancel current if (cancelCurrent) { final Boast cachedGlobalBoast = getGlobalBoast(); if ((cachedGlobalBoast != null)) { cachedGlobalBoast.cancel(); } } // save an instance of this current notification setGlobalBoast(this); internalToast.show(); } }
而不是取消敬酒。 改变文字。 例如
Toast t; t = Toast.makeText(this, "hi", 3000); t.show();
当你需要不同的敬酒然后使用
t.setText("bye"); t.show();
如果你想解雇吐司只需要调用t.cancel()
您可以通过在Toast对象上调用cancel（）来取消各个Toasts。 AFAIK，但你没有办法取消所有未完成的敬酒。
尝试保留最后的敬酒时间戳，并且不允许任何新的敬酒，直到超时时间已过。
就像是：
private static final long TOAST_TIMEOUT_MS = 2000; // tweak this constant private static long lastToastTime = 0; public void onButtonClicked() { long now = System.currentTimeMillis(); if (lastToastTime + TOAST_TIMEOUT_MS < now) { Toast.makeText(...).show(); lastToastTime = now; } }
在用户退出应用程序后，我不会担心一杯吐露的东西 – 这是一个非常标准的行为。
