Automatically pick the best render target

This changeset adds a new option, on by default, which causes the
layout editor to always pick the best rendering target. The best
rendering target is typically the most recent one. This option can be
toggled in the rendering target drop down menu (but it applies
globally), and choosing a specific rendering target turns it off.

Change-Id: I53e48a38741f364f2b68525a4898aca69b1ae7b1

3 files changed, 89 insertions, 22 deletions

diff --git a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/Configuration.java b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/Configuration.java
index 29dcb34..8ca0c26 100644
--- a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/Configuration.java
+++ b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/Configuration.java
@@ -37,6 +37,7 @@ import com.android.ide.common.resources.configuration.VersionQualifier;
 import com.android.ide.eclipse.adt.AdtPlugin;
 import com.android.ide.eclipse.adt.internal.editors.layout.gle2.RenderService;
 import com.android.ide.eclipse.adt.internal.editors.manifest.ManifestInfo;
+import com.android.ide.eclipse.adt.internal.preferences.AdtPrefs;
 import com.android.ide.eclipse.adt.internal.resources.ResourceHelper;
 import com.android.ide.eclipse.adt.internal.resources.manager.ProjectResources;
 import com.android.ide.eclipse.adt.internal.resources.manager.ResourceManager;
@@ -832,27 +833,32 @@ public class Configuration {
                     }
                     locale = Locale.create(language, region);
 
-                    target = stringToTarget(chooser, values[1]);
-
-                    // See if we should "correct" the rendering target to a better version.
-                    // If you're using a pre-release version of the render target, and a
-                    // final release is available and installed, we should switch to that
-                    // one instead.
-                    if (target != null) {
-                        AndroidVersion version = target.getVersion();
-                        List<IAndroidTarget> targetList = chooser.getTargetList();
-                        if (version.getCodename() != null && targetList != null) {
-                            int targetApiLevel = version.getApiLevel() + 1;
-                            for (IAndroidTarget t : targetList) {
-                                if (t.getVersion().getApiLevel() == targetApiLevel
-                                        && t.isPlatform()) {
-                                    target = t;
-                                    break;
+                    if (AdtPrefs.getPrefs().isAutoPickRenderTarget()) {
+                        target = ConfigurationMatcher.findDefaultRenderTarget(chooser);
+                    } else {
+                        String targetString = values[1];
+                        target = stringToTarget(chooser, targetString);
+                        // See if we should "correct" the rendering target to a
+                        // better version. If you're using a pre-release version
+                        // of the render target, and a final release is
+                        // available and installed, we should switch to that
+                        // one instead.
+                        if (target != null) {
+                            AndroidVersion version = target.getVersion();
+                            List<IAndroidTarget> targetList = chooser.getTargetList();
+                            if (version.getCodename() != null && targetList != null) {
+                                int targetApiLevel = version.getApiLevel() + 1;
+                                for (IAndroidTarget t : targetList) {
+                                    if (t.getVersion().getApiLevel() == targetApiLevel
+                                            && t.isPlatform()) {
+                                        target = t;
+                                        break;
+                                    }
                                 }
                             }
+                        } else {
+                            target = ConfigurationMatcher.findDefaultRenderTarget(chooser);
                         }
-                    } else {
-                        target = ConfigurationMatcher.findDefaultRenderTarget(chooser);
                     }
                 }
 
@@ -878,7 +884,7 @@ public class Configuration {
         }
         try {
             // Generate a persistent string from locale+target
-            StringBuilder sb = new StringBuilder();
+            StringBuilder sb = new StringBuilder(32);
             Locale locale = getLocale();
             if (locale != null) {
                 // locale[0]/[1] can be null sometimes when starting Eclipse
diff --git a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/TargetMenuListener.java b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/TargetMenuListener.java
index c0f361c..71905f7 100644
--- a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/TargetMenuListener.java
+++ b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/editors/layout/configuration/TargetMenuListener.java
@@ -18,6 +18,7 @@ package com.android.ide.eclipse.adt.internal.editors.layout.configuration;
 
 import com.android.annotations.NonNull;
 import com.android.annotations.Nullable;
+import com.android.ide.eclipse.adt.internal.preferences.AdtPrefs;
 import com.android.sdklib.AndroidVersion;
 import com.android.sdklib.IAndroidTarget;
 
@@ -40,17 +41,36 @@ import java.util.RandomAccess;
 class TargetMenuListener extends SelectionAdapter {
     private final ConfigurationChooser mConfigChooser;
     private final IAndroidTarget mTarget;
+    private final boolean mPickBest;
 
     TargetMenuListener(
             @NonNull ConfigurationChooser configChooser,
-            @Nullable IAndroidTarget target) {
+            @Nullable IAndroidTarget target,
+            boolean pickBest) {
         mConfigChooser = configChooser;
         mTarget = target;
+        mPickBest = pickBest;
     }
 
     @Override
     public void widgetSelected(SelectionEvent e) {
-        mConfigChooser.selectTarget(mTarget);
+        IAndroidTarget target = mTarget;
+        AdtPrefs prefs = AdtPrefs.getPrefs();
+        if (mPickBest) {
+            boolean autoPick = prefs.isAutoPickRenderTarget();
+            autoPick = !autoPick;
+            prefs.setAutoPickRenderTarget(autoPick);
+            if (autoPick) {
+                target = ConfigurationMatcher.findDefaultRenderTarget(mConfigChooser);
+            } else {
+                // Turn it off, but keep current target until another one is chosen
+                return;
+            }
+        } else {
+            // Manually picked some other target: turn off auto-pick
+            prefs.setAutoPickRenderTarget(false);
+        }
+        mConfigChooser.selectTarget(target);
         mConfigChooser.onRenderingTargetChange();
     }
 
@@ -61,6 +81,16 @@ class TargetMenuListener extends SelectionAdapter {
         List<IAndroidTarget> targets = chooser.getTargetList();
         boolean haveRecent = false;
 
+        MenuItem menuItem = new MenuItem(menu, SWT.CHECK);
+        menuItem.setText("Automatically Pick Best");
+        menuItem.addSelectionListener(new TargetMenuListener(chooser, null, true));
+        if (AdtPrefs.getPrefs().isAutoPickRenderTarget()) {
+            menuItem.setSelection(true);
+        }
+
+        @SuppressWarnings("unused")
+        MenuItem separator = new MenuItem(menu, SWT.SEPARATOR);
+
         // Process in reverse order: most important targets first
         assert targets instanceof RandomAccess;
         for (int i = targets.size() - 1; i >= 0; i--) {
@@ -84,7 +114,7 @@ class TargetMenuListener extends SelectionAdapter {
                 item.setSelection(true);
             }
 
-            item.addSelectionListener(new TargetMenuListener(chooser, target));
+            item.addSelectionListener(new TargetMenuListener(chooser, target, false));
         }
 
         Rectangle bounds = combo.getBounds();
diff --git a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/preferences/AdtPrefs.java b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/preferences/AdtPrefs.java
index 8a2877e..002dc63 100644
--- a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/preferences/AdtPrefs.java
+++ b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/preferences/AdtPrefs.java
@@ -73,6 +73,7 @@ public final class AdtPrefs extends AbstractPreferenceInitializer {
     public final static String PREFS_FIX_LEGACY_EDITORS = AdtPlugin.PLUGIN_ID + ".fixLegacyEditors"; //$NON-NLS-1$
     public final static String PREFS_SHARED_LAYOUT_EDITOR = AdtPlugin.PLUGIN_ID + ".sharedLayoutEditor"; //$NON-NLS-1$
     public final static String PREFS_PREVIEWS = AdtPlugin.PLUGIN_ID + ".previews"; //$NON-NLS-1$
+    public final static String PREFS_AUTO_PICK_TARGET = AdtPlugin.PLUGIN_ID + ".autoPickTarget"; //$NON-NLS-1$
 
     /** singleton instance */
     private final static AdtPrefs sThis = new AdtPrefs();
@@ -103,6 +104,7 @@ public final class AdtPrefs extends AbstractPreferenceInitializer {
     private boolean mLintOnExport;
     private AttributeSortOrder mAttributeSort;
     private boolean mSharedLayoutEditor;
+    private boolean mAutoPickTarget;
     private RenderPreviewMode mPreviewMode = RenderPreviewMode.NONE;
     private int mPreferXmlEditor;
 
@@ -259,6 +261,10 @@ public final class AdtPrefs extends AbstractPreferenceInitializer {
             mSharedLayoutEditor = mStore.getBoolean(PREFS_SHARED_LAYOUT_EDITOR);
         }
 
+        if (property == null || PREFS_AUTO_PICK_TARGET.equals(property)) {
+            mAutoPickTarget = mStore.getBoolean(PREFS_AUTO_PICK_TARGET);
+        }
+
         if (property == null || PREFS_PREVIEWS.equals(property)) {
             mPreviewMode = RenderPreviewMode.NONE;
             String previewMode = mStore.getString(PREFS_PREVIEWS);
@@ -501,6 +507,7 @@ public final class AdtPrefs extends AbstractPreferenceInitializer {
         store.setDefault(PREFS_SPACE_BEFORE_CLOSE, true);
         store.setDefault(PREFS_LINT_ON_SAVE, true);
         store.setDefault(PREFS_LINT_ON_EXPORT, true);
+        store.setDefault(PREFS_AUTO_PICK_TARGET, true);
 
         // Defaults already handled; no need to write into map:
         //store.setDefault(PREFS_ATTRIBUTE_SORT, AttributeSortOrder.LOGICAL.key);
@@ -579,4 +586,28 @@ public final class AdtPrefs extends AbstractPreferenceInitializer {
             store.setToDefault(PREFS_PREVIEWS);
         }
     }
+
+    /**
+     * Sets whether auto-pick render target mode is enabled.
+     *
+     * @return whether the layout editor should automatically pick the best render target
+     */
+    public boolean isAutoPickRenderTarget() {
+        return mAutoPickTarget;
+    }
+
+    /**
+     * Sets whether auto-pick render target mode is enabled.
+     *
+     * @param autoPick if true, auto pick the best render target in the layout editor
+     */
+    public void setAutoPickRenderTarget(boolean autoPick) {
+        mAutoPickTarget = autoPick;
+        IPreferenceStore store = AdtPlugin.getDefault().getPreferenceStore();
+        if (autoPick) {
+            store.setToDefault(PREFS_AUTO_PICK_TARGET);
+        } else {
+            store.setValue(PREFS_AUTO_PICK_TARGET, autoPick);
+        }
+    }
 }