一 、背景

使用自定义DialogFragment实现弹窗效果时，边缘透明图片作为背景图片，依然存在不透明背景；

QQ截图20180428154111.png

修复后：

QQ截图20180428153910.png

二、实现

因为项目中多个地方使用到DialogFragment，所以稍作了一下封装：

import android.app.Dialog;

import android.graphics.Color;

import android.graphics.drawable.ColorDrawable;

import android.os.Bundle;

import android.support.annotation.Nullable;

import android.support.v4.app.DialogFragment;

import android.support.v7.app.AlertDialog;

import android.util.DisplayMetrics;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import butterknife.ButterKnife;

import butterknife.Unbinder;

/**

* Created by Ljt on 2018/4/27

*/

public abstract class BaseDislogFragment extends DialogFragment {

private boolean isShow = false;

private Unbinder unbinder;

public boolean isShow() {

return isShow;

}

public void setShow(boolean show) {

isShow = show;

}

/**

* 显示弹窗信息

* @param savedInstanceState

* @param builder

*/

protected abstract void displayDialog(Bundle savedInstanceState, AlertDialog.Builder builder);

/**

* 设置布局文件

* @return

*/

protected abstract int getLayoutId();

protected abstract boolean isCanceledOnTouchOutside();

protected abstract boolean isTransparent();

@Nullable

@Override

public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {

View rootView = super.onCreateView(inflater, container, savedInstanceState);

return rootView;

}

@Override

public void onStart() {

super.onStart();

if (isTransparent()) {

//设置背景半透明

DisplayMetrics dm = new DisplayMetrics();

getActivity().getWindowManager().getDefaultDisplay().getMetrics(dm);

getDialog().getWindow().setLayout(dm.widthPixels, getDialog().getWindow().getAttributes().height);

getDialog().getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));

}

//getDialog().setCancelable(false);//这个会屏蔽掉返回键

getDialog().setCanceledOnTouchOutside(isCanceledOnTouchOutside());

}

@Override

public Dialog onCreateDialog(Bundle savedInstanceState) {

AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());

LayoutInflater inflater = getActivity().getLayoutInflater();

final View view = inflater.inflate(getLayoutId(), null);

unbinder = ButterKnife.bind(this, view);

builder.setView(view);

displayDialog(savedInstanceState,builder);

return builder.create();

}

@Override

public void onDestroyView() {

super.onDestroyView();

unbinder.unbind();

}

public void dismissDialog() {

if (isShow) {

this.dismiss();

}

}

}

所以事实上，这里最终使用的还是使用onCreateDialog()方法返回AlertDialog来呈现自定义布局弹窗；

主要的实现背景透明效果，使用如下代码：

DisplayMetrics dm = new DisplayMetrics();

getActivity().getWindowManager().getDefaultDisplay().getMetrics(dm);

getDialog().getWindow().setLayout(dm.widthPixels, getDialog().getWindow().getAttributes().height);

getDialog().getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));

BaseDialogFragment的子类使用起来就只关注与具体差异的实现就好了：

import android.os.Bundle;

import android.support.v4.app.FragmentManager;

import android.view.View;

import android.widget.ImageView;

import android.widget.RelativeLayout;

import android.widget.TextView;

//这里删除了部分带有APP报名路径的类的导入

import butterknife.BindView;

/**

* Created by Ljt on 2018/4/26

*/

public class RewardDialogFragment extends BaseDislogFragment {

@BindView(R.id.img_reward_bg)

ImageView imgRewardBg;

@BindView(R.id.tv_reward_sum)

TextView tvRewardSum;

@BindView(R.id.tv_reward_receive)

TextView tvRewardReceive;

@BindView(R.id.rl_reward_content)

RelativeLayout rlRewardContent;

@BindView(R.id.img_reward_close)

ImageView imgRewardClose;

private Callback callback;

public interface Callback {

void onClose();

void onReceive();

}

public void setCallback(Callback pCallBack){

this.callback = pCallBack;

}

public void show(FragmentManager fragmentManager) {

if (this.isAdded())return;

show(fragmentManager, "RewardDialogFragment");

setShow(false);

Settings.setFirstReward(false);

}

@Override

protected void displayDialog(Bundle savedInstanceState, android.support.v7.app.AlertDialog.Builder builder) {

imgRewardClose.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

if (callback != null)callback.onClose();

dismiss();

}

});

tvRewardReceive.setOnClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

if (callback != null)callback.onReceive();

dismiss();

}

});

}

@Override

protected int getLayoutId() {

return R.layout.fragment_dialog_reward;

}

@Override

protected boolean isCanceledOnTouchOutside() {

return false;

}

@Override

protected boolean isTransparent() {

return true;

}

@Override

public void onDestroy() {

super.onDestroy();

callback = null;

}

}

！！！请确认当中的AlertDialog使用android.support.v7.app.AlertDialog下的；否则在Android 5.0以下版本，依然是不透明。