From 8d742fbfd20d78bd7dff4bae1d36012e6746037f Mon Sep 17 00:00:00 2001
From: voodoo <luowenyue5@gmail.com>
Date: Tue, 8 Feb 2022 22:23:15 +0800
Subject: [PATCH] added feature that clearing current selection if max
 selectable is 1 #808

---
 .../main/java/com/zhihu/matisse/SelectionCreator.java | 11 +++++++++++
 .../zhihu/matisse/internal/entity/SelectionSpec.java  |  2 ++
 .../internal/model/SelectedItemCollection.java        | 10 +++++++++-
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/matisse/src/main/java/com/zhihu/matisse/SelectionCreator.java b/matisse/src/main/java/com/zhihu/matisse/SelectionCreator.java
index c85c3d34d..a6500c9ce 100755
--- a/matisse/src/main/java/com/zhihu/matisse/SelectionCreator.java
+++ b/matisse/src/main/java/com/zhihu/matisse/SelectionCreator.java
@@ -346,6 +346,17 @@ public SelectionCreator setOnCheckedListener(@Nullable OnCheckedListener listene
         return this;
     }
 
+    /**
+     * Set if selection should change on case where maxSelectable is 1
+     *
+     * @param changeSelectionOnSelectingOne
+     * @return {@link SelectionCreator} for fluent API.
+     */
+    public SelectionCreator setChangeSelectionOnSelectingOne(boolean changeSelectionOnSelectingOne) {
+        mSelectionSpec.changeSelectionOnSelectingOne = changeSelectionOnSelectingOne;
+        return this;
+    }
+
     /**
      * Start to select media and wait for result.
      *
diff --git a/matisse/src/main/java/com/zhihu/matisse/internal/entity/SelectionSpec.java b/matisse/src/main/java/com/zhihu/matisse/internal/entity/SelectionSpec.java
index 70806270c..0dd8f2701 100755
--- a/matisse/src/main/java/com/zhihu/matisse/internal/entity/SelectionSpec.java
+++ b/matisse/src/main/java/com/zhihu/matisse/internal/entity/SelectionSpec.java
@@ -61,6 +61,7 @@ public final class SelectionSpec {
     public boolean showPreview;
     public Drawable audioThumbnail;
     public Drawable audioPlaceholder;
+    public boolean changeSelectionOnSelectingOne;
 
     private SelectionSpec() {
     }
@@ -100,6 +101,7 @@ private void reset() {
         showPreview = true;
         audioThumbnail = null;
         audioPlaceholder = null;
+        changeSelectionOnSelectingOne = false;
     }
 
     public boolean singleSelectionModeEnabled() {
diff --git a/matisse/src/main/java/com/zhihu/matisse/internal/model/SelectedItemCollection.java b/matisse/src/main/java/com/zhihu/matisse/internal/model/SelectedItemCollection.java
index b0abaa6c6..fab2511ec 100755
--- a/matisse/src/main/java/com/zhihu/matisse/internal/model/SelectedItemCollection.java
+++ b/matisse/src/main/java/com/zhihu/matisse/internal/model/SelectedItemCollection.java
@@ -177,7 +177,10 @@ public boolean isSelected(Item item) {
     }
 
     public IncapableCause isAcceptable(Item item) {
-        if (maxSelectableReached()) {
+        if (shouldRemoveSelection()) {
+            mItems.clear();
+        }
+        else if (maxSelectableReached()) {
             int maxSelectable = currentMaxSelectable();
             String cause;
 
@@ -211,6 +214,11 @@ public boolean maxSelectableReached() {
         return mItems.size() == currentMaxSelectable();
     }
 
+    public boolean shouldRemoveSelection() {
+        SelectionSpec spec = SelectionSpec.getInstance();
+        return mItems.size() == 1 && currentMaxSelectable() == 1 && spec.changeSelectionOnSelectingOne;
+    }
+
     // depends
     private int currentMaxSelectable() {
         SelectionSpec spec = SelectionSpec.getInstance();