在项目中遇到，图片下载的方法封装在imageUtils类中，下载要用Toast到提醒。如果在activity中可以用runOnUiThread和Handler来显示提醒，现在不是在activity，又不想在imageUtils中用Handler。所以想到如果有个全局的Toast就方便多了。

先上效果图：

Toast.gif

全局Toast:

1. 支持默认格式，自上向下布局为ImageView，TextView，TextView，三个控件可以自由组合显示或隐藏

2. 支持Top，Center，Bottom的位置显示

3. 支持多样的显示格式，可以传入自定义的layout的View

4. 共用一个Toast对象，防止多次Toast重叠并显示时间累加，该控件近保留最后一次的设置和显示。

5. 最好在自定义的Application中new该Toast，Activity，Fragment，Adapter中都可以直接调用。

自定义Toast代码如下， 用静态内部类Builder设置Toast的样式:

public class FlexibleToast {

public static final int GRAVITY_BOTTOM = 0;

public static final int GRAVITY_CENTER = 1;

public static final int GRAVITY_TOP = 2;

public static final int TOAST_SHORT = 0;

public static final int TOAST_LONG = 1;

private Context mContext;

private Toast flexibleToast;

public void toastShow(Builder builder) {

if (flexibleToast == null) {

flexibleToast = new Toast(mContext);

}

// toast position

if (builder.mGravity == GRAVITY_CENTER) {

flexibleToast.setGravity(Gravity.CENTER | Gravity.CENTER_VERTICAL, 0, 0);

} else if (builder.mGravity == GRAVITY_TOP) {

flexibleToast.setGravity(Gravity.TOP | Gravity.CENTER_VERTICAL, 0, Tools.dip2px(mContext, 20));

} else {

flexibleToast.setGravity(Gravity.BOTTOM | Gravity.CENTER_VERTICAL, 0, Tools.dip2px(mContext, 20));

}

if (builder.mDuration == TOAST_LONG) {

flexibleToast.setDuration(Toast.LENGTH_LONG);

} else {

flexibleToast.setDuration(Toast.LENGTH_SHORT);

}

if (builder.hasCustomerView && builder.mCustomerView != null) {

flexibleToast.setView(builder.mCustomerView);

} else {

flexibleToast.setView(builder.mDefaultView);

}

flexibleToast.show();

}

public FlexibleToast(Context context) {

mContext = context;

}

/**

* 控制Toast的显示样式

*/

public static class Builder {

private View mDefaultView;

private View mCustomerView;

private ImageView mIvImage;

private TextView mTvFirst;

private TextView mTvSecond;

private View dividerFirst;

private View dividerSecond;

private int mDuration = Toast.LENGTH_SHORT;// 0 short, 1 long

private int mGravity = 0;

private boolean hasCustomerView = false; // 是否使用自定义layout

/**

* 使用全局的ApplicationContext进行初始化

* @param context

*/

public Builder(Context context) {

mDefaultView = LayoutInflater.from(context).inflate(R.layout.layout_toast_flexible, null);

mIvImage = (ImageView) mDefaultView.findViewById(R.id.iv_img);

mTvFirst = (TextView) mDefaultView.findViewById(R.id.tv_text_first);

mTvSecond = (TextView) mDefaultView.findViewById(R.id.tv_text_second);

dividerFirst = mDefaultView.findViewById(R.id.divider_first);

dividerSecond = mDefaultView.findViewById(R.id.divider_second);

}

public Builder setImageResource(int resId) {

this.mIvImage.setImageResource(resId);

this.mIvImage.setVisibility(View.VISIBLE);

this.dividerFirst.setVisibility(View.VISIBLE);

return this;

}

public Builder setFirstText(String firstText) {

this.mTvFirst.setText(firstText);

this.mTvFirst.setVisibility(View.VISIBLE);

this.dividerSecond.setVisibility(View.VISIBLE);

return this;

}

public Builder setSecondText(String secondText) {

this.mTvSecond.setText(secondText);

this.mTvSecond.setVisibility(View.VISIBLE);

return this;

}

public Builder setDuration(int duration) {

this.mDuration = duration;

return this;

}

public Builder setGravity(int gravity) {

this.mGravity = gravity;

return this;

}

/**

* 为Toast指定自定义的layout，此时上面对ImageView和TextView的设置失效。

* @param customerView

* @return

*/

public Builder setCustomerView(View customerView) {

this.mCustomerView = customerView;

this.hasCustomerView = true;

return this;

}

}

}

在Application中初始化自定义Toast:

创建自定义ToastflexibleToast = new FlexibleToast(this)，然后提供方法toastShowByBuilder()供调用传builder设置样式

public class BaseApp extends Application {

// 全局的 handler 对象

private final Handler appHandler = new Handler();

// 全局的 Toast 对象

private FlexibleToast flexibleToast;

private static BaseApp instance;

public static void setInstance(BaseApp instance) {

BaseApp.instance = instance;

}

public static BaseApp getInstance() {

return instance;

}

@Override

public void onCreate() {

super.onCreate();

setInstance(this);

flexibleToast = new FlexibleToast(this);

Log.i("TAG","主线程"+Thread.currentThread().getId());

}

public Handler getAppHandler() {

return appHandler;

}

public void toastShowByBuilder(final FlexibleToast.Builder builder) {

if (Looper.myLooper() != Looper.getMainLooper()) {

getAppHandler().post(new Runnable() {

@Override

public void run() {

flexibleToast.toastShow(builder);

}

});

} else {

flexibleToast.toastShow(builder);

}

}

}

下面分别列出Toast在屏幕中间、子线程、自定义显示的用法：

设置显示位置在屏幕中间：

FlexibleToast.Builder builder = new FlexibleToast.Builder(MainActivity.this)

.setGravity(FlexibleToast.GRAVITY_CENTER)

.setFirstText("中间").setSecondText("提醒");

BaseApp.getInstance().toastShowByBuilder(builder);

在子线程显示：

new Thread(new Runnable() {

@Override

public void run() {

Log.i("TAG","子线程");

FlexibleToast.Builder builder = new FlexibleToast.Builder(MainActivity.this)

.setGravity(FlexibleToast.GRAVITY_BOTTOM)

.setFirstText("底部").setSecondText("提醒");

BaseApp.getInstance().toastShowByBuilder(builder);

}

}).start();

自定义样式：

final View customview= LayoutInflater

.from(this)

.inflate(R.layout.item,null,false);

FlexibleToast.Builder builder = new FlexibleToast.Builder(MainActivity.this)

.setGravity(FlexibleToast.GRAVITY_BOTTOM)

.setCustomerView(customview);

BaseApp.getInstance().toastShowByBuilder(builder);

git上源代码地址，欢迎指出错误哈！

SnackBar是 Android Support Library 22.2.0 里面新增提供的一个控件。SnackBar默认从屏幕底部弹出，像Toast一样会自动消失，当然也可以手动划出屏幕消失。Toast是不能交互的，而如果需要，SnackBar默认是可以添加一个点击事件的。效果如下：

snackbar.gif

普通snackbar代码如下：

snckbar可以设置回调setCallback(new Snackbar.Callback())显示和取消分别处理，不知道snackbar的用法，请点击

还在用Toast？试试Snackbar!

Snackbar snackbar = Snackbar.make(button3,"normalSnackbar", LENGTH_LONG).setActionTextColor(getResources().getColor(R.color.white))

/* .setCallback(new Snackbar.Callback() {

@Override

public void onDismissed(Snackbar snackbar, int event) {

super.onDismissed(snackbar, event);

FlexibleToast.Builder builder = new FlexibleToast.Builder(MainActivity.this)

.setGravity(FlexibleToast.GRAVITY_CENTER)

.setFirstText("回调dismiss");

BaseApp.getInstance().toastShowByBuilder(builder);

}

@Override

public void onShown(Snackbar snackbar) {

super.onShown(snackbar);

FlexibleToast.Builder builder = new FlexibleToast.Builder(MainActivity.this)

.setGravity(FlexibleToast.GRAVITY_CENTER).setFirstText("回调show");

BaseApp.getInstance().toastShowByBuilder(builder);

}

})*/

.setAction("点击", new View.OnClickListener() {

@Override

public void onClick(View v) {

FlexibleToast.Builder builder = new FlexibleToast.Builder(MainActivity.this)

.setGravity(FlexibleToast.GRAVITY_CENTER).setFirstText("中间toast");

BaseApp.getInstance().toastShowByBuilder(builder);

}

});

snackbar.show();

自定义snackbar代码如下：

Snackbar snackbar = Snackbar.make(findViewById(R.id.button4),"自定义",Snackbar.LENGTH_LONG);

View view = snackbar.getView();

ViewGroup.LayoutParams Params = view.getLayoutParams();

view.setBackgroundColor(getResources().getColor(R.color.colorPrimary));

CoordinatorLayout.LayoutParams layoutParams = new CoordinatorLayout.LayoutParams(Params.width,Params.height);

layoutParams.gravity = Gravity.TOP;

// TODO 为什么设置居中没反应

// layoutParams.gravity = Gravity.CENTER;为什么设置居中没反应

view.setLayoutParams(layoutParams);

view.setBackgroundColor(getResources().getColor(R.color.colorPrimary));

// view.setAnimation();

ImageView imageView = new ImageView(MainActivity.this);

imageView.setLayoutParams(new ViewGroup.LayoutParams(100,100));

imageView.setImageDrawable(getResources().getDrawable(R.drawable.lufei));

Snackbar.SnackbarLayout snackbarLayout = (Snackbar.SnackbarLayout) view;

snackbarLayout.setOrientation(LinearLayout.HORIZONTAL);

snackbarLayout.addView(imageView);

snackbar.setAction("点击", new View.OnClickListener() {

@Override

public void onClick(View v) {

FlexibleToast.Builder builder = new FlexibleToast.Builder(MainActivity.this).setGravity(FlexibleToast.GRAVITY_CENTER).setFirstText("自定义的snackbar");

BaseApp.getInstance().toastShowByBuilder(builder);

}

}).show();

git上源代码地址，欢迎指出错误哈！

想要设置snackbar剧中显示layoutParams.gravity = Gravity.CENTER;居然没有效果，不知道哪里出错了，有哪个兄弟看到了能指出，不胜感激！！！