手写一个通用加载中、显示数据、加载失败、空数据的LoadingView框架。

定义3个布局：加载中，加载失败，空数据

加载中:

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#ffffff"

android:clickable="true">

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center"

android:indeterminate="true" />

加载失败:

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#ffffff"

android:clickable="true"

android:orientation="vertical">

android:id="@+id/error_retry"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center"

android:gravity="center"

android:src="@drawable/loading_retry" />

空数据:

android:layout_width="match_parent"

android:layout_height="match_parent"

android:background="#ffffff"

android:clickable="true"

android:orientation="vertical">

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center"

android:src="@drawable/loading_empty" />

自定义一个LoadingView:

package com.sample.loadingview.widget;

import android.content.Context;

import android.content.res.TypedArray;

import android.support.annotation.AttrRes;

import android.support.annotation.NonNull;

import android.support.annotation.Nullable;

import android.util.AttributeSet;

import android.util.SparseArray;

import android.view.LayoutInflater;

import android.view.View;

import android.widget.FrameLayout;

import android.widget.ImageView;

import com.sample.loadingview.R;

public class LoadingView extends FrameLayout {

private int emptyLayoutId, errorLayoutId, loadingLayoutId;

private View contentView, emptyView, errorView, loadingView;

private LayoutInflater mInflater;

private SparseArray views = new SparseArray<>();

public LoadingView(@NonNull Context context) {

this(context, null);

}

public LoadingView(@NonNull Context context, @Nullable AttributeSet attrs) {

this(context, attrs, 0);

}

public LoadingView(@NonNull Context context, @Nullable AttributeSet attrs, @AttrRes int defStyleAttr) {

super(context, attrs, defStyleAttr);

TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.LoadLayout);

emptyLayoutId = a.getResourceId(R.styleable.LoadLayout_emptyView, R.layout.loading_empty);

errorLayoutId = a.getResourceId(R.styleable.LoadLayout_errorView, R.layout.loading_error);

loadingLayoutId = a.getResourceId(R.styleable.LoadLayout_loadingView, R.layout.loading_load);

mInflater = LayoutInflater.from(getContext());

a.recycle();

loadingView = mInflater.inflate(loadingLayoutId, null);

}

@Override

protected void onFinishInflate() {

super.onFinishInflate();

if (getChildCount() < 1) {

throw new RuntimeException("content view can not be null");

}

contentView = getChildAt(0);

if (loadingView.getVisibility() != GONE)

loadingView.setVisibility(GONE);

addView(loadingView);

views.put(loadingLayoutId, loadingView);

}

public void showError() {

errorView = views.get(errorLayoutId);

if (errorView == null) {

errorView = mInflater.inflate(errorLayoutId, null);

addView(errorView);

views.put(errorLayoutId, errorView);

final ImageView errorRetry = (ImageView) errorView.findViewById(R.id.error_retry);

errorRetry.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

if (mOnRetryClickListener != null)

mOnRetryClickListener.onClick(errorRetry);

}

});

}

if (errorView.getVisibility() != VISIBLE)

errorView.setVisibility(VISIBLE);

for (int i = 0, len = views.size(); i < len; i++) {

int key = views.keyAt(i);

if (key != errorLayoutId) {

View view = views.valueAt(i);

if (view != null)

if (view.getVisibility() != GONE)

view.setVisibility(GONE);

}

}

}

public void showEmpty() {

emptyView = views.get(emptyLayoutId);

if (emptyView == null) {

emptyView = mInflater.inflate(emptyLayoutId, null);

addView(emptyView);

views.put(emptyLayoutId, emptyView);

}

if (emptyView.getVisibility() != VISIBLE)

emptyView.setVisibility(VISIBLE);

for (int i = 0, len = views.size(); i < len; i++) {

int key = views.keyAt(i);

if (key != emptyLayoutId) {

View view = views.valueAt(i);

if (view != null)

if (view.getVisibility() != GONE)

view.setVisibility(GONE);

}

}

}

public void showLoading() {

loadingView = views.get(loadingLayoutId);

if (loadingView.getVisibility() != VISIBLE)

loadingView.setVisibility(VISIBLE);

for (int i = 0, len = views.size(); i < len; i++) {

int key = views.keyAt(i);

if (key != loadingLayoutId) {

View view = views.valueAt(i);

if (view != null)

if (view.getVisibility() != GONE)

view.setVisibility(GONE);

}

}

}

public void showContent() {

for (int i = 0, len = views.size(); i < len; i++) {

View view = views.valueAt(i);

if (view != null)

if (view.getVisibility() != GONE)

view.setVisibility(GONE);

}

}

private OnClickListener mOnRetryClickListener;

public void setOnRetryClickListener(OnClickListener onRetryClickListener) {

this.mOnRetryClickListener = onRetryClickListener;

}

}

定义attrs.xml

以上就这么些代码，接下来我们测试一下

Activity

package com.sample.loadingview;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

import android.view.View;

import android.widget.Button;

import android.widget.Toast;

import com.sample.loadingview.widget.LoadingView;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

private LoadingView loading_view;

private Button btn_loading;

private Button btn_content;

private Button btn_error;

private Button btn_empty;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

loading_view = (LoadingView) findViewById(R.id.loading_view);

btn_loading = (Button) findViewById(R.id.btn_loading);

btn_content = (Button) findViewById(R.id.btn_content);

btn_error = (Button) findViewById(R.id.btn_error);

btn_empty = (Button) findViewById(R.id.btn_empty);

//设置加载错误的点击事件

loading_view.setOnRetryClickListener(new View.OnClickListener() {

@Override

public void onClick(View v) {

Toast.makeText(MainActivity.this, "重新加载", Toast.LENGTH_SHORT).show();

loading_view.showLoading();

}

});

btn_loading.setOnClickListener(this);

btn_content.setOnClickListener(this);

btn_error.setOnClickListener(this);

btn_empty.setOnClickListener(this);

}

@Override

public void onClick(View v) {

switch (v.getId()) {

case R.id.btn_loading:

loading_view.showLoading();//显示加载界面

break;

case R.id.btn_content:

loading_view.showContent();//显示内容界面

break;

case R.id.btn_error:

loading_view.showError();//显示错误界面

break;

case R.id.btn_empty:

loading_view.showEmpty();//显示空数据界面

break;

}

}

}

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脚本之家。