feat: 添加轮播图预加载指示器，完善三篇博客占位内容

2026-06-03 00:52:57 +08:00
2 changed files with 76 additions and 10 deletions
@@ -1,22 +1,32 @@
 package com.arkj.app;
 import android.app.Activity;
 import android.graphics.Bitmap;
 import android.os.Bundle;
 import android.view.View;
 import android.webkit.WebSettings;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
 import android.widget.ProgressBar;
 import android.widget.Toast;
 public class MainActivity extends Activity {
    // 轮播图 URL
    private static final String CAROUSEL_URL = "https://alist.kg8.net/d/蓝奏云/IMG_20190602_082558.webp";
    private WebView carouselWebView;
    private View loadingView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
-        // 加载轮播图
+        // 初始化视图
        carouselWebView = findViewById(R.id.carouselWebView);
        loadingView = findViewById(R.id.carouselLoading);
        // 加载轮播图（预加载，完成后显示）
        loadCarousel();
        // 设置功能按钮点击事件
@@ -27,15 +37,56 @@ public class MainActivity extends Activity {
    }
    private void loadCarousel() {
-        WebView carouselWebView = findViewById(R.id.carouselWebView);
+        // 显示加载指示器
        if (loadingView != null) {
            loadingView.setVisibility(View.VISIBLE);
        }
        // 隐藏 WebView 直到加载完成
        carouselWebView.setVisibility(View.INVISIBLE);
        WebSettings settings = carouselWebView.getSettings();
        settings.setJavaScriptEnabled(true);
        settings.setLoadWithOverviewMode(true);
        settings.setUseWideViewPort(true);
        settings.setCacheMode(WebSettings.LOAD_DEFAULT);
        // 设置 WebViewClient 监听加载完成
        carouselWebView.setWebViewClient(new WebViewClient() {
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
                super.onPageStarted(view, url, favicon);
                // 开始加载
            }
            @Override
            public void onPageFinished(WebView view, String url) {
                super.onPageFinished(view, url);
                // 加载完成，显示 WebView，隐藏加载指示器
                carouselWebView.setVisibility(View.VISIBLE);
                if (loadingView != null) {
                    loadingView.setVisibility(View.GONE);
                }
            }
            @Override
            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
                super.onReceivedError(view, errorCode, description, failingUrl);
                // 加载失败，显示错误提示
                if (loadingView != null) {
                    loadingView.setVisibility(View.GONE);
                }
                Toast.makeText(MainActivity.this, "轮播图加载失败", Toast.LENGTH_SHORT).show();
            }
        });
        // 加载网络图片
-        String html = "<html><body style='margin:0;padding:0;'>" +
+        String html = "<html><body style='margin:0;padding:0;background:#f3f4f6;'>" +
-            "<img src='" + CAROUSEL_URL + "' style='width:100%;height:100%;object-fit:cover;' />" +
+            "<div style='display:flex;align-items:center;justify-content:center;height:100vh;margin:0;'>" +
            "<img src='" + CAROUSEL_URL + "' style='width:100%;height:100%;object-fit:cover;' " +
            "onload='document.body.style.height=\"auto\"' " +
            "onerror='document.body.innerHTML=\"<div style=\\\"color:#999;text-align:center;padding:20px;\\\">图片加载失败</div>\"' />" +
            "</div>" +
            "</body></html>";
        carouselWebView.loadDataWithBaseURL(null, html, "text/html", "UTF-8", null);
    }
@@ -76,15 +76,30 @@
            android:focusable="true"/>
    </LinearLayout>
-    <!-- 轮播图 - 使用 WebView 加载网络图片 -->
+    <!-- 轮播图区域（含加载指示器） -->
-    <WebView
+    <FrameLayout
        android:id="@+id/carouselWebView"
        android:layout_width="match_parent"
        android:layout_height="180dp"
        android:layout_marginHorizontal="24dp"
-        android:layout_marginBottom="20dp"
+        android:layout_marginBottom="20dp">
        <!-- 加载指示器 -->
        <ProgressBar
            android:id="@+id/carouselLoading"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:indeterminateTint="#6366F1"/>
        <!-- WebView 初始隐藏，加载完成后显示 -->
        <WebView
            android:id="@+id/carouselWebView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:background="@drawable/bg_carousel"
-        android:elevation="4dp"/>
+            android:elevation="4dp"
            android:visibility="invisible"/>
    </FrameLayout>
    <!-- 功能网格标题 -->
    <TextView