fix(music): 修复输入丢失、焦点残留与拖拽状态脱离框架

src/main/java/top/fpsmaster/modules/music/AudioEngine.java

@@ -139,33 +139,61 @@ private void playLoop(File file, Runnable onEnded) throws Exception {
                 applyGain(line);
 
                 double bytesPerMs = decoded.getFrameRate() * decoded.getFrameSize() / 1000.0;
+                int frameSize = Math.max(1, decoded.getFrameSize());
 
                 if (startMs > 0) {
-                    skipDecoded(din, (long) (startMs * bytesPerMs));
+                    // PCM has to be skipped a whole frame at a time — one frame is channels × 2 bytes
+                    // for 16-bit audio. Landing mid-frame shifts every following sample by a byte or
+                    // two, so the high/low halves of each sample and the left/right channels are read
+                    // out of position and the result is white noise. startMs * bytesPerMs is only a
+                    // multiple of the frame size by luck, which is why it happened on some seeks and
+                    // not others, and why seeking again "fixed" it.
+                    long skipBytes = (long) (startMs * bytesPerMs);
+                    skipBytes -= skipBytes % frameSize;
+                    skipDecoded(din, skipBytes);
                 }
                 long posBytes = 0;
                 byte[] buf = new byte[4096];
+                // Bytes left over from the previous read that do not yet complete a frame.
+                int carry = 0;
 
                 while (!stopped) {
                     long seek = pendingSeekMs;
                     if (seek >= 0) {
                         pendingSeekMs = -1;
                         startMs = seek;
                         seekBreak = true;
+                        // Discard whatever is still queued in the line before tearing it down. The
+                        // buffer holds PCM decoded at the *old* position; closing without flushing
+                        // lets it play out as a burst of noise just before the new stream starts.
+                        // stop() first so flush() is not racing an active playback pointer.
+                        line.stop();
+                        line.flush();
                         break;
                     }
                     if (paused) {
                         Thread.sleep(30);
                         continue;
                     }
-                    int n = din.read(buf, 0, buf.length);
+                    int n = din.read(buf, carry, buf.length - carry);
                     if (n < 0) {
                         endedNaturally = true;
                         break;
                     }
-                    line.write(buf, 0, n);
-                    posBytes += n;
-                    positionMs = startMs + (long) (posBytes / bytesPerMs);
+                    // SourceDataLine.write is documented as undefined unless the length is a whole
+                    // number of frames, and the decoder does not promise frame-aligned reads. Write
+                    // only the complete frames and carry the remainder into the next read.
+                    int available = carry + n;
+                    int writable = available - (available % frameSize);
+                    if (writable > 0) {
+                        line.write(buf, 0, writable);
+                        posBytes += writable;
+                        positionMs = startMs + (long) (posBytes / bytesPerMs);
+                    }
+                    carry = available - writable;
+                    if (carry > 0) {
+                        System.arraycopy(buf, writable, buf, 0, carry);
+                    }
                 }
             } finally {
                 closeQuietly(line, din, fileIn);

src/main/java/top/fpsmaster/ui/screens/music/MusicScreen.java

@@ -39,6 +39,9 @@ private enum Tab {DISCOVER, PLAYLISTS, SEARCH, LYRICS}
     // 间距系统：统一用 PAD 作为面板内边距基准
     private static final float PAD = 20f;
 
+    /** Sidebar content (≈215px) + player bar (46px) + margin. Below this the sidebar overflows. */
+    private static final float MIN_PANEL_HEIGHT = 300f;
+
     // 配色（跟随 ClickGUI 主题，见 refreshTheme）
     private static final int DIM = 0xCC000000;
     private static final int BADGE = 0xFFD9A441;
@@ -82,6 +85,9 @@ private void refreshTheme() {
     private boolean loginOpen = false;
     private QrLoginState lastQrState = null;
 
+    private static final String PROGRESS_CAPTURE = "music.progress";
+    private static final String VOLUME_CAPTURE = "music.volume";
+
     private boolean draggingProgress = false;
     private float previewFrac = 0;
     private boolean draggingVolume = false;
@@ -98,14 +104,27 @@ public void initGui() {
         f18 = FPSMaster.fontManager.s18;
         f20 = FPSMaster.fontManager.s20;
         f24 = FPSMaster.fontManager.s24;
-        searchField = new TextField(f16, "搜索歌曲 / 歌手…", CARD, TEXT, 60, new Runnable() {
-            @Override
-            public void run() {
-                doSearch();
-            }
-        });
-        qqUin = new TextField(f14, "musicid (uin)", CARD, TEXT, 32);
-        qqKey = new TextField(f14, "musickey (qm_keyst)", CARD, TEXT, 256);
+
+        // initGui also runs on every window resize, and rebuilding the fields there threw away whatever
+        // the user had typed — including a pasted QQ musickey, which is tedious to obtain. Keep the
+        // existing instances instead of recreating and re-populating them: setText() runs
+        // setCursorPosition(), which derives the scroll offset from getWidth(), and width is only
+        // assigned inside drawTextBox() — so on a field that has never been drawn it reads 0, pushes
+        // lineScrollOffset past the end of the text, and the box renders empty from then on.
+        if (searchField == null) {
+            searchField = new TextField(f16, "搜索歌曲 / 歌手…", CARD, TEXT, 60, new Runnable() {
+                @Override
+                public void run() {
+                    doSearch();
+                }
+            });
+        }
+        if (qqUin == null) {
+            qqUin = new TextField(f14, "musicid (uin)", CARD, TEXT, 32);
+        }
+        if (qqKey == null) {
+            qqKey = new TextField(f14, "musickey (qm_keyst)", CARD, TEXT, 256);
+        }
     }
 
     private int accent() {
@@ -119,15 +138,20 @@ public void render(int mouseX, int mouseY, float partialTicks) {
         refreshTheme();
         int mx = getMouseX();
         int my = getMouseY();
-        ScaledGuiScreen.PointerEvent pe = consumePressInBounds(0, 0, guiWidth, guiHeight, 0);
-        boolean click = pe != null;
+        // Peek, don't consume: whichever widget actually contains the press claims it inside in().
+        ScaledGuiScreen.PointerEvent pe = peekAnyPress();
+        boolean click = pe != null && pe.button == 0;
         int cx = click ? pe.x : -1;
         int cy = click ? pe.y : -1;
 
         Rects.fill(0, 0, guiWidth, guiHeight, DIM);
 
         float pw = Math.min(guiWidth - 30, 500);
-        float ph = Math.min(guiHeight - 30, 316);
+        // The sidebar's content height is fixed (title + 3 nav rows + source header + 2 source rows +
+        // the bottom-aligned login button), so a panel shorter than this let the source rows spill past
+        // contentBottom and land on top of the player bar — where a single click hit both, starting
+        // playback and switching source at once. Keep the panel tall enough that it cannot happen.
+        float ph = Math.max(Math.min(guiHeight - 30, 316), MIN_PANEL_HEIGHT);
         float px = (guiWidth - pw) / 2f;
         float py = (guiHeight - ph) / 2f;
 
@@ -219,6 +243,12 @@ private float sidebarNav(float x, float baseY, float w, String label, Tab t, int
         if (in(cx, cy, ix, baseY, iw, ih) && tab != t) {
             tab = t;
             scroll = 0;
+            // The search box only gets a chance to lose focus while the search tab is rendering, so
+            // without this it stays focused after navigating away and keeps swallowing keystrokes into
+            // a field that is no longer on screen.
+            if (searchField != null) {
+                searchField.setFocused(false);
+            }
         }
         return baseY + ih + 3;
     }
@@ -576,31 +606,35 @@ private void drawSlider(float x, float y, float w, float frac, int mx, int my, i
             Rects.rounded(knobX - 3, ty + trackH / 2f - 3, 6, 6, 3, 0xFFFFFFFF);
         }
 
-        boolean down = isMouseDown(0);
-        boolean startHere = in(cx, cy, x, y - 4, w, 11);
+        // Routed through the shared drag capture rather than a private boolean, so the capture is
+        // released centrally when the button goes up — including when it goes up outside the window,
+        // which a locally-tracked flag never learns about and which used to leave the knob glued to
+        // the cursor after an alt-tab.
+        // in() establishes the hit and claims the press; acquireDrag then takes ownership without
+        // asking for a second press that no longer exists. Using beginPointerCapture here instead made
+        // the two consumption paths race for the same event, which is why dragging only worked
+        // sometimes. Release is still handled centrally on button-up, so an alt-tab cannot strand it.
+        Object captureId = isProgress ? PROGRESS_CAPTURE : VOLUME_CAPTURE;
+        if (in(cx, cy, x, y - 4, w, 11)) {
+            acquireDrag(captureId, 0);
+        }
+        boolean capturing = isPointerCapturedBy(captureId, 0);
 
         if (isProgress) {
-            if (startHere) {
+            if (capturing) {
                 draggingProgress = true;
                 previewFrac = clamp01((mx - x) / w);
-            }
-            if (draggingProgress) {
-                if (down) {
-                    previewFrac = clamp01((mx - x) / w);
-                } else {
-                    m.seekFraction(previewFrac);
-                    draggingProgress = false;
-                }
+            } else if (draggingProgress) {
+                // Commit on release, not continuously — seeking every frame would thrash the decoder.
+                m.seekFraction(previewFrac);
+                draggingProgress = false;
             }
         } else {
-            if (startHere) draggingVolume = true;
-            if (draggingVolume) {
-                if (down) {
-                    int v = Math.round(clamp01((mx - x) / w) * 100);
-                    m.setVolume(v);
-                } else {
-                    draggingVolume = false;
-                }
+            if (capturing) {
+                draggingVolume = true;
+                m.setVolume(Math.round(clamp01((mx - x) / w) * 100));
+            } else {
+                draggingVolume = false;
             }
         }
     }
@@ -805,8 +839,23 @@ private void clampScroll(float total, float viewH) {
         if (scroll < 0) scroll = 0;
     }
 
-    private static boolean in(int cx, int cy, float x, float y, float w, float h) {
-        return cx >= 0 && cx >= x && cx < x + w && cy >= y && cy < y + h;
+    /**
+     * Hit-test that also claims the press.
+     *
+     * <p>{@code render} used to consume the whole screen up front and hand the raw coordinates to
+     * every widget, which then re-tested them independently. Two consequences: overlapping widgets all
+     * fired on one press (clicking play while the sidebar had overflowed onto it both started playback
+     * and switched source), and {@code beginPointerCapture} could never acquire, because the press it
+     * needs had already been eaten — which is why the progress bar could not be dragged.
+     *
+     * <p>Claiming here makes a press belong to exactly one widget, and leaves it available to the
+     * capture-based sliders when no plain widget wants it.
+     */
+    private boolean in(int cx, int cy, float x, float y, float w, float h) {
+        if (cx < 0 || cx < x || cx >= x + w || cy < y || cy >= y + h) {
+            return false;
+        }
+        return consumePressInBounds(x, y, w, h, 0) != null;
     }
 
     private static float clamp01(float v) {

src/main/java/top/fpsmaster/utils/render/gui/ScaledGuiScreen.java

@@ -238,6 +238,18 @@ public boolean beginDrag(Object owner, int button, float x, float y, float width
         return dragState.acquire(owner, button);
     }
 
+    /**
+     * Takes drag ownership without re-consuming a press.
+     *
+     * <p>{@link #beginDrag} both claims a press and acquires, which is right for widgets that hit-test
+     * by calling it. A caller that has already established the hit some other way — and consumed the
+     * press doing so — would otherwise find no press left to claim and never acquire. Release still
+     * happens centrally on button-up.
+     */
+    public boolean acquireDrag(Object owner, int button) {
+        return dragState.acquire(owner, button);
+    }
+
     public boolean isDragging(Object owner) {
         return dragState.isDragging(owner) && isMouseDown(dragState.getButton());
     }