Simulate shift key press?

[balex25]

Hi,

Is it possible to simulate a shift press? I need to get hasShiftDown() true from Screen.class (try to get a tooltip with shift press and without from itemStack#getTooltipLines()). 

Also, I tried with follow, but it did not trigger:

// Simulate holding down the shift key
Minecraft.getInstance().player.setShiftKeyDown(true);
Minecraft.getInstance().options.keyShift.setDown(true);
KeyMapping.set(Minecraft.getInstance().options.keyShift.getKey(), true);

Leave code here, maybe some still need it.

ScreenMixin.class

import com.mojang.blaze3d.platform.InputConstants;
import net.minecraft.client.Minecraft;
import net.minecraft.client.gui.screens.Screen;
import org.spongepowered.asm.mixin.Mixin;
import org.spongepowered.asm.mixin.injection.At;
import org.spongepowered.asm.mixin.injection.Inject;
import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
import ShiftStateUtility;

@Mixin(Screen.class)
public class ScreenMixin {

    @Inject(method = "hasShiftDown", at = @At("HEAD"), cancellable = true)
    private static void onHasShiftDown(CallbackInfoReturnable<Boolean> cir) {
        if(ShiftStateUtility.shouldShiftBeDown) {
            cir.setReturnValue(ShiftStateUtility.shouldShiftBeDown);
        } else {
            // Call a method that checks the actual key state.
            cir.setReturnValue(checkActualShiftState());
        }
    }

    @Inject(method = "hasControlDown", at = @At("HEAD"), cancellable = true)
    private static void hasControlDown(CallbackInfoReturnable<Boolean> cir) {
        if(ShiftStateUtility.shouldControlBeDown) {
            cir.setReturnValue(ShiftStateUtility.shouldControlBeDown);
        } else {
            // Call a method that checks the actual key state.
            cir.setReturnValue(checkActualControlState());
        }
    }

    @Inject(method = "hasAltDown", at = @At("HEAD"), cancellable = true)
    private static void hasAltDown(CallbackInfoReturnable<Boolean> cir) {
        if(ShiftStateUtility.shouldAltBeDown) {
            cir.setReturnValue(ShiftStateUtility.shouldAltBeDown);
        } else {
            // Call a method that checks the actual key state.
            cir.setReturnValue(checkActualAltState());
        }
    }

    private static boolean checkActualShiftState() {
        return InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 340) || InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 344);
    }

    private static boolean checkActualControlState() {
        if (Minecraft.ON_OSX) {
            return InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 343) || InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 347);
        } else {
            return InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 341) || InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 345);
        }
    }

    private static boolean checkActualAltState() {
        return InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 342) || InputConstants.isKeyDown(Minecraft.getInstance().getWindow().getWindow(), 346);
    }
}

ShiftStateUtility.class

public class ShiftStateUtility {
    public static boolean shouldShiftBeDown = false;
    public static boolean shouldControlBeDown = false;
    public static boolean shouldAltBeDown = false;
}

Usage:

ShiftStateUtility.shouldShiftBeDown = true / false;
ShiftStateUtility.shouldControlBeDown = true / false;
ShiftStateUtility.shouldAltBeDown = true / false;

The default behavior of hasShiftDown, hasAltDown, and hasControlDown still work as default, and you can control if want to simulate a press of any key.

Edited November 3, 2023 by balex25
Fixed it using Mixin on the hasShiftDown method.

[Luis_ST]

Did you tried to output your values in the console? Are the (mixin) methods called? Is your Mixin class registered?