当Android开发处理错误信息时，经常会以Dialog的形式显示错误信息，但是每次都new一个Dialog，很麻烦，也增加程序的开销，所以今天就分享一种自定义单例AlertDialog

public class AlertDialog {

private static AlertDialog alertDialog = null;

private Context context;

private Dialog dialog;

private LinearLayout lLayout_bg;

private TextView txt_title;

private TextView txt_msg;

private Button btn_neg;

private Button btn_pos;

private ImageView img_line;

private Display display;

private boolean showTitle = false;

private boolean showMsg = false;

private boolean showPosBtn = false;

private boolean showNegBtn = false;

public static AlertDialog getInstance(Context context){

if (alertDialog==null){

synchronized (AlertDialog.class) {

if (alertDialog == null) {

alertDialog = new AlertDialog(context).builder();

}

}

}

return alertDialog;

}

public AlertDialog(Context context) {

this.context = context;

WindowManager windowManager = (WindowManager) context

.getSystemService(Context.WINDOW_SERVICE);

display = windowManager.getDefaultDisplay();

}

public AlertDialog builder() {

// 获取Dialog布局

View view = LayoutInflater.from(context).inflate(R.layout.view_alertdialog, null);

// 获取自定义Dialog布局中的控件

lLayout_bg = (LinearLayout) view.findViewById(R.id.lLayout_bg);

txt_title = (TextView) view.findViewById(R.id.txt_title);

txt_title.setVisibility(View.GONE);

txt_msg = (TextView) view.findViewById(R.id.txt_msg);

txt_msg.setVisibility(View.GONE);

btn_neg = (Button) view.findViewById(R.id.btn_neg);

btn_neg.setVisibility(View.GONE);

btn_pos = (Button) view.findViewById(R.id.btn_pos);

btn_pos.setVisibility(View.GONE);

img_line = (ImageView) view.findViewById(R.id.img_line);

img_line.setVisibility(View.GONE);

// 定义Dialog布局和参数

dialog = new Dialog(context, R.style.AlertDialogStyle);

dialog.setContentView(view);

// 调整dialog背景大小

lLayout_bg.setLayoutParams(new FrameLayout.LayoutParams((int) (display

.getWidth() * 0.85), LayoutParams.WRAP_CONTENT));

return this;

}

public AlertDialog setTitle(String title) {

showTitle = true;

if ("".equals(title)) {

txt_title.setText("标题");

} else {

txt_title.setText(title);

}

return this;

}

public AlertDialog setMsg(String msg) {

showMsg = true;

if ("".equals(msg)) {

txt_msg.setText("内容");

} else {

txt_msg.setText(msg);

}

return this;

}

public AlertDialog setMsg(int rId) {

showMsg = true;

txt_msg.setText(rId);

return this;

}

public AlertDialog setCancelable(boolean cancel) {

dialog.setCancelable(cancel);

return this;

}

public AlertDialog setPositiveButton(String text,

final OnClickListener listener) {

showPosBtn = true;

if ("".equals(text)) {

btn_pos.setText("确定");

} else {

btn_pos.setText(text);

}

btn_pos.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

if(listener!=null) {

listener.onClick(v);

}

dialog.dismiss();

}

});

return this;

}

public AlertDialog setNegativeButton(String text,

final OnClickListener listener) {

showNegBtn = true;

if ("".equals(text)) {

btn_neg.setText("取消");

} else {

btn_neg.setText(text);

}

btn_neg.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

if(listener!=null) {

listener.onClick(v);

}

dialog.dismiss();

}

});

return this;

}

private void setLayout() {

if (!showTitle && !showMsg) {

txt_title.setText("");

txt_title.setVisibility(View.VISIBLE);

}

if (showTitle) {

txt_title.setVisibility(View.VISIBLE);

}

if (showMsg) {

txt_msg.setVisibility(View.VISIBLE);

}

if (!showPosBtn && !showNegBtn) {

btn_pos.setText("确定");

btn_pos.setVisibility(View.VISIBLE);

btn_pos.setBackgroundResource(R.drawable.alertdialog_single_selector);

btn_pos.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

dialog.dismiss();

}

});

}

if (showPosBtn && showNegBtn) {

btn_pos.setVisibility(View.VISIBLE);

btn_pos.setBackgroundResource(R.drawable.alertdialog_right_selector);

btn_neg.setVisibility(View.VISIBLE);

btn_neg.setBackgroundResource(R.drawable.alertdialog_left_selector);

img_line.setVisibility(View.VISIBLE);

}

if (showPosBtn && !showNegBtn) {

btn_pos.setVisibility(View.VISIBLE);

btn_pos.setBackgroundResource(R.drawable.alertdialog_single_selector);

}

if (!showPosBtn && showNegBtn) {

btn_neg.setVisibility(View.VISIBLE);

btn_neg.setBackgroundResource(R.drawable.alertdialog_single_selector);

}

}

public void show() {

setLayout();

dialog.show();

}

}

布局文件view_alertdialog.xml

android:id="@+id/lLayout_bg"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:background="@drawable/alert_bg"

android:orientation="vertical">

android:id="@+id/txt_title"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginLeft="15dp"

android:layout_marginRight="15dp"

android:layout_marginTop="15dp"

android:gravity="center"

android:text="提示"

android:textColor="@color/black"

android:textSize="18dp" />

android:id="@+id/txt_msg"

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:layout_marginLeft="15dp"

android:layout_marginRight="15dp"

android:layout_marginTop="10dp"

android:layout_marginBottom="10dp"

android:gravity="center"

android:text="您确定要退出吗？"

android:textColor="@color/black"

android:textSize="16dp" />

android:layout_width="match_parent"

android:layout_height="0.5dp"

android:layout_marginTop="10dp"

android:background="@color/alertdialog_line" />

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:orientation="horizontal">

android:id="@+id/btn_neg"

android:layout_width="wrap_content"

android:layout_height="43dp"

android:layout_weight="1"

android:background="@drawable/alertdialog_left_selector"

android:gravity="center"

android:text="确定"

android:textColor="@color/bigtextcolor"

android:textSize="16sp" />

android:id="@+id/img_line"

android:layout_width="0.5dp"

android:layout_height="43dp"

android:background="@color/alertdialog_line" />

android:id="@+id/btn_pos"

android:layout_width="wrap_content"

android:layout_height="43dp"

android:layout_weight="1"

android:background="@drawable/alertdialog_right_selector"

android:gravity="center"

android:text="取消"

android:textColor="@color/themecolor"

android:textSize="16sp" />

效果显示

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程圈。